September 2015 - Allocations-admins - mailman3.cels.anl.gov

New LCRC report submitted for protein_e-wire
by support＠lcrc.anl.gov 04 Sep '15

04 Sep '15

Full project report at https://accounts.lcrc.anl.gov/reporting/project/2015/?project=protein_e-wire

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Re: [allocations-admins] [LCRC Accounts] Project Request: CEES-II-Wolverton
by Bair, Raymond A. 04 Sep '15

04 Sep '15

This project also looks OK. Suggest allocating 100K for FY15 on Blues, and telling them they will also need to submit a FY16 request. Category: Physical Sciences Subcategory: Materials Science POC: Larry Curtiss ----------------------------------------- Ray Bair Computing, Environment, and Life Sciences Argonne National Laboratory and the University of Chicago TCS Building 240, Room 4122 9700 South Cass Avenue Argonne, IL 60439 email: rbair(at)anl.gov Phone: (630)252-5751 On 9/4/15, 11:42 AM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of accounts(a)lcrc.anl.gov" <allocations-admins-bounces(a)lcrc.anl.gov on behalf of accounts(a)lcrc.anl.gov> wrote: >Hello, > >A new project on the LCRC cluster has been requested. Please forward >the information on to the LCRC Allocation sub-committee. > > Applicant's name: Chris Wolverton >Applicant's institution: ANL > Applicant's division: Computing, Environment, and Life Sciences > Project Name: CEES-II-Wolverton > Project title: DFT Computation of Hybrid and Li-ion Battery >Materials > Associated funding: CEES-II EFRC > Other Systems: > Science: Recent experiments have shown that lithium and >oxygen can be electrochemically removed from Li5FeO4 (5Li2OÂ·Fe2O3) and >re-accommodated during discharge, creating the possibility of its use as >a high-capacity electrode in a hybrid Li-ion/Liâ€“O2 electrochemical >cell. Taking this novel chemistry as a model, we use density functional >theory (DFT) within a high-throughput framework to screen for analogous >reactions in other materials. We also are interested in determining the >mass tranport kinetics of the phase transformations in these materials. > Project description: 1. Thermodynamics studies including electronic >structure calculations, phase transformation calculations for new Li-ion >and hybrid Li-ion/Li-O2 battery chemistries. >2. Kinetics studies including defect formation energy calculations, >ab-initio molecular dynamics, nudged elastic band calculations and >kinetic Monte Carlo simulations for Li/O transport in hybrid materials >including Li-Fe-O and Li-Mn-O. >3. New high-throughput DFT discovery of novel hybrid Metal-ion/Metal-O2 >battery chemistries, novel battery anode/cathode materials. >4. Structure predictions of new phases observed in the >charging/discharging of transition metal oxides. > >Computational methods employed will largely be DFT-based, multiprocessor >jobs. > Industry partnership: > Project URL: > Requested allocation: 500000 > Q1: 0 > Q2: 0 > Q3: 0 > Q4: 500000 > Justification: Our group has considerable experience with >high-throughput DFT computation, and have demonstrated this in the Open >Quantum Materials Database (OQMD). OQMD is available online at oqmd.org, >and consists of a database of >300,000 DFT calculations of known and >hypothetical inorganic materials. > Storage requirements: > > >The requester has used undetermined amount hours of their initial startup >project. > >In addition to approving an initial amount, please specify a Category >and Subcategory for this project. For a list of the current selection >of approved categories, please see: > > https://wiki.lcrc.anl.gov/wiki/Processes/Categories > >Once the Allocation committee has approved the project, please go to >the Project Management page to create it: > >https://accounts.lcrc.anl.gov/projects.php > >Thank You, >The LCRC Accounts System

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Re: [allocations-admins] [LCRC Accounts] Project Request: Bubble_superlattice
by Bair, Raymond A. 04 Sep '15

04 Sep '15

PPS. 750K is way too much to use before 9/30. Please let t hem know that they will need to submit another request for FY16. Lets start them at 100K Ray On 9/4/15, 12:10 PM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of Bair, Raymond A." <allocations-admins-bounces(a)lcrc.anl.gov on behalf of rbair(a)anl.gov> wrote: >P.S. > >Category: Physical Sciences > >Subcategory: Materials Science > >POC: Elia Merzari > > > > > >On 9/4/15, 12:03 PM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of >Bair, Raymond A." <allocations-admins-bounces(a)lcrc.anl.gov on behalf of >rbair(a)anl.gov> wrote: > >>This looks fine to me, to start on Blues. >> >>John low - are you part of this project effort? >> >>Ray >> >> >> >>On 9/4/15, 8:37 AM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of >>accounts(a)lcrc.anl.gov" <allocations-admins-bounces(a)lcrc.anl.gov on behalf >>of accounts(a)lcrc.anl.gov> wrote: >> >>>Hello, >>> >>>A new project on the LCRC cluster has been requested. Please forward >>>the information on to the LCRC Allocation sub-committee. >>> >>> Applicant's name: Zhigang Mei >>>Applicant's institution: ANL >>> Applicant's division: NE >>> Project Name: Bubble_superlattice >>> Project title: Atomistic Simulation of Fission Gas Bubble >>>Superlattice in Irradiated Materials >>> Associated funding: NNSA >>> Other Systems: Carbon at CNM >>> Science: The accumulation of gaseous species in nuclear >>>fuel leads to deleterious microstructural changes that are of utmost >>>concern to both fission reactor applications [Trinkaus, J. Nucl. Mater. >>>323 (2003) 229]. Inert gas elements â€“ such as helium, xenon and >>>krypton >>>- are generated due to fission reactions in nuclear fuel. In general, >>>the >>>precipitation of gaseous species into gas-filled bubbles leads to >>>volumetric swelling in fuels. According to conventional nucleation >>>theory, in the early stages of irradiation, gas atoms diffuse throughout >>>the crystal and begin to form clusters due to their insolubility in the >>>solid. This clustering can initiate either by chance encounters of the >>>wandering gas atoms, or by gas-atom trapping at microstructural >>>segregation sites such as grain boundaries (GBs) [Rest, J. Nucl. Mater. >>>207 (1993) 192]. The subsequent growth or shrinkage of a gas bubble is >>>governed by the fluxes of vacancies, interstitials, and gas atoms to or >>> away from the bubble surface. If gas bubbles are located on sinks (such >>>as GBs), they may grow indefinitely to the point of interconnection, >>>thus >>>lead to rapid fission gas release to the exterior of fuel. It is found >>>that the formation of micro-sized fission-gas bubbles at GBs is the >>>major >>>reason leading to the fuel swellings at high fission density, while >>>nano-sized intragranular gas bubbles have negligible contribution to the >>>overall fuel swelling. Therefore a major task for fuel development is to >>>control the fission gas bubble microstructures and to retain more >>>fission-gas bubble inside fuel grains at high fission density. Some of >>>the proposed approaches include (i) Enhancing the solubility of fission >>>gas in fuel by modifying the fuel composition and (ii) Increasing the >>>grain size in the fuel by heat treatment. So far, these approaches have >>>not been well tested and their effects on the nucleation and growth of >>>fission gas bubbles are not clear. >>>Recent experiments by Gan et al show that fission gas bubbles form fcc >>>superlattice in the irradiated bcc U-7Mo dispersion fuel [Miller et al., >>>J. Nucl. Mater. 458 (2015) 115]. Typical bubble size and spacing in >>>these >>>bubble superlattices are in the range of 2.75-4.5 nm and 10-12 nm, >>>respectively. Although ordered bubble superlattice has also been seen in >>>ion-irradiated materials, common observations show that superlattice >>>will >>>primarily form in the same structure and crystal orientation as the host >>>material. Meanwhile the formation of bubble superlattice is >>>counterintuitive to the fact that fission gas is randomly generated in >>>lattice and gas bubbles should be nucleated in a random manner >>>initially. >>>Our own TEM characterization of Xe irradiated U-Mo however shows that >>>gas >>>bubbles were randomly distributed in grain instead of forming ordered >>>superlattice. >>>The goal of this proposal is to investigate the potential mechanisms of >>>the formation and collapse of the Xe bubble superlattice in irradiated >>>U-Mo alloys using atomistic simulations. We hope this study will provide >>>a microscopic model of the nucleation and growth of gas bubble inside >>>fuel grains and therefore better control of gas bubble microstructure >>>under radiation. >>> >>> Project description: We will use molecular dynamics (MD) to >>>investigate the potential mechanism of the formation of Xe bubbles >>>superlattice in U-Mo alloys. The obtained simulation results will be >>>compared to the microstructure characterized by TEM in irradiated U-7Mo >>>fuels. A ternary U-Mo-Xe potential has been previously developed by >>>Smirnova based on embedded atom method (EAM) [Smirnova et al. Modelling >>>Simul. Mater. Sci. Eng. 21 (2013) 035011]. However our test shows that >>>this potential cannot predict the accurate formation energy of Xe >>>defects >>>in U-Mo. Therefore, we will use the so-called force matching method as >>>implemented in potfit [Brommer, Modelling Simul Mater Sci Eng 15 (2007) >>>295] to develop a new potential for U-Mo-Xe based modified EAM (MEAM). >>>To >>>build a potential suitable for the simulation of a complicated ternary >>>system, we have to prepare an extensive set of reference configurations >>>representing all kinds of possible structures. Each configuration is cor >>> responding to one of the possible states of the U-Mo-Xe system. VASP >>>will be used to calculate energy, force and stress of the reference >>>configurations with atoms up to 150. The total computational time using >>>DFT will be 150000 CPU-hours. >>>To model different configurations of Xe gas bubbles in U-Mo alloys, a >>>120Ã—120Ã—120 cell (40nmÃ—40nmÃ—40nm) based on bcc structure will be >>>constructed. About 3.5 million atoms will be introduced in the >>>simulation >>>box, which allows adding up to 110 gas bubbles with size around 2.5 nm. >>>We will compare the energetics of different bubble superlattices, such >>>as >>>cubic, fcc, bcc, hcp and disordered bubbles configurations. We will also >>>investigate the effect of Mo concentration on the retention of Xe atoms >>>in the lattice. Two different alloys, i.e., U-7wt%Mo and U-10wt%Mo, will >>>be studied and be compared to pure bcc Mo and U cases. Meanwhile, >>>temperature plays an important role in governing the fluxes of >>>vacancies, >>>interstitials and gas atoms to or away from the bubble surface. The >>>interested temperature range is between 300 K and 1000 K. In experiment, >>>it was observed that the gas bubble superlattice collapses at high >>>fission density. A major effect of fission on the microstructure >>> is creating a large amount of Frenkel pair defects in the lattice. >>>Vacancy can provide efficient diffusion channels for Xe atoms. In this >>>work, we will investigate the effect of five parameters (Xe >>>concentration, Xe bubble configuration, Mo concentration, temperature, >>>and Frenkel pair concentration) on the stability of gas bubble >>>superlattices introduced in U-xMo alloys. By systematic analysis of the >>>bubble superlatticeâ€™s microstructure and their energetics, we will be >>>able to correlate the key parameters to the formation of bubble >>>superlattice, and provide a potential mechanism of its formation in >>>U-Mo. >>>Combining all the parameters, we will expect about 50 production jobs. >>>Our initial test shows that a single MD simulation for 1 nano-second >>>takes more than 12000 CPU-hours (256 CPUÃ—24 hours). We therefore >>>request >>>the total computational time of 750000 CPU-hours. >>> >>> Industry partnership: >>> Project URL: >>> Requested allocation: 750000 >>> Q1: 0 >>> Q2: 0 >>> Q3: 0 >>> Q4: 750000 >>> Justification: The main calculations are performed by high >>>efficient molecular dynamics code LAMMPS. The parallel efficiency test >>>for this code shows that it can be well scaled to up to tens of >>>thousands >>>of CPUs. Other DFT calculations will be performed by VASP, which is one >>>of the widely used DFT code. >>> Storage requirements: 1 TB >>> >>> >>>The requester has used undetermined amount hours of their initial >>>startup >>>project. >>> >>>In addition to approving an initial amount, please specify a Category >>>and Subcategory for this project. For a list of the current selection >>>of approved categories, please see: >>> >>> https://wiki.lcrc.anl.gov/wiki/Processes/Categories >>> >>>Once the Allocation committee has approved the project, please go to >>>the Project Management page to create it: >>> >>>https://accounts.lcrc.anl.gov/projects.php >>> >>>Thank You, >>>The LCRC Accounts System >> >>_______________________________________________ >>allocations-admins mailing list >>allocations-admins(a)lcrc.anl.gov >>https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins > >_______________________________________________ >allocations-admins mailing list >allocations-admins(a)lcrc.anl.gov >https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins

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Re: [allocations-admins] [LCRC Accounts] Project Request: Bubble_superlattice
by Bair, Raymond A. 04 Sep '15

04 Sep '15

P.S. Category: Physical Sciences Subcategory: Materials Science POC: Elia Merzari On 9/4/15, 12:03 PM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of Bair, Raymond A." <allocations-admins-bounces(a)lcrc.anl.gov on behalf of rbair(a)anl.gov> wrote: >This looks fine to me, to start on Blues. > >John low - are you part of this project effort? > >Ray > > > >On 9/4/15, 8:37 AM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of >accounts(a)lcrc.anl.gov" <allocations-admins-bounces(a)lcrc.anl.gov on behalf >of accounts(a)lcrc.anl.gov> wrote: > >>Hello, >> >>A new project on the LCRC cluster has been requested. Please forward >>the information on to the LCRC Allocation sub-committee. >> >> Applicant's name: Zhigang Mei >>Applicant's institution: ANL >> Applicant's division: NE >> Project Name: Bubble_superlattice >> Project title: Atomistic Simulation of Fission Gas Bubble >>Superlattice in Irradiated Materials >> Associated funding: NNSA >> Other Systems: Carbon at CNM >> Science: The accumulation of gaseous species in nuclear >>fuel leads to deleterious microstructural changes that are of utmost >>concern to both fission reactor applications [Trinkaus, J. Nucl. Mater. >>323 (2003) 229]. Inert gas elements â€“ such as helium, xenon and krypton >>- are generated due to fission reactions in nuclear fuel. In general, the >>precipitation of gaseous species into gas-filled bubbles leads to >>volumetric swelling in fuels. According to conventional nucleation >>theory, in the early stages of irradiation, gas atoms diffuse throughout >>the crystal and begin to form clusters due to their insolubility in the >>solid. This clustering can initiate either by chance encounters of the >>wandering gas atoms, or by gas-atom trapping at microstructural >>segregation sites such as grain boundaries (GBs) [Rest, J. Nucl. Mater. >>207 (1993) 192]. The subsequent growth or shrinkage of a gas bubble is >>governed by the fluxes of vacancies, interstitials, and gas atoms to or >> away from the bubble surface. If gas bubbles are located on sinks (such >>as GBs), they may grow indefinitely to the point of interconnection, thus >>lead to rapid fission gas release to the exterior of fuel. It is found >>that the formation of micro-sized fission-gas bubbles at GBs is the major >>reason leading to the fuel swellings at high fission density, while >>nano-sized intragranular gas bubbles have negligible contribution to the >>overall fuel swelling. Therefore a major task for fuel development is to >>control the fission gas bubble microstructures and to retain more >>fission-gas bubble inside fuel grains at high fission density. Some of >>the proposed approaches include (i) Enhancing the solubility of fission >>gas in fuel by modifying the fuel composition and (ii) Increasing the >>grain size in the fuel by heat treatment. So far, these approaches have >>not been well tested and their effects on the nucleation and growth of >>fission gas bubbles are not clear. >>Recent experiments by Gan et al show that fission gas bubbles form fcc >>superlattice in the irradiated bcc U-7Mo dispersion fuel [Miller et al., >>J. Nucl. Mater. 458 (2015) 115]. Typical bubble size and spacing in these >>bubble superlattices are in the range of 2.75-4.5 nm and 10-12 nm, >>respectively. Although ordered bubble superlattice has also been seen in >>ion-irradiated materials, common observations show that superlattice will >>primarily form in the same structure and crystal orientation as the host >>material. Meanwhile the formation of bubble superlattice is >>counterintuitive to the fact that fission gas is randomly generated in >>lattice and gas bubbles should be nucleated in a random manner initially. >>Our own TEM characterization of Xe irradiated U-Mo however shows that gas >>bubbles were randomly distributed in grain instead of forming ordered >>superlattice. >>The goal of this proposal is to investigate the potential mechanisms of >>the formation and collapse of the Xe bubble superlattice in irradiated >>U-Mo alloys using atomistic simulations. We hope this study will provide >>a microscopic model of the nucleation and growth of gas bubble inside >>fuel grains and therefore better control of gas bubble microstructure >>under radiation. >> >> Project description: We will use molecular dynamics (MD) to >>investigate the potential mechanism of the formation of Xe bubbles >>superlattice in U-Mo alloys. The obtained simulation results will be >>compared to the microstructure characterized by TEM in irradiated U-7Mo >>fuels. A ternary U-Mo-Xe potential has been previously developed by >>Smirnova based on embedded atom method (EAM) [Smirnova et al. Modelling >>Simul. Mater. Sci. Eng. 21 (2013) 035011]. However our test shows that >>this potential cannot predict the accurate formation energy of Xe defects >>in U-Mo. Therefore, we will use the so-called force matching method as >>implemented in potfit [Brommer, Modelling Simul Mater Sci Eng 15 (2007) >>295] to develop a new potential for U-Mo-Xe based modified EAM (MEAM). To >>build a potential suitable for the simulation of a complicated ternary >>system, we have to prepare an extensive set of reference configurations >>representing all kinds of possible structures. Each configuration is cor >> responding to one of the possible states of the U-Mo-Xe system. VASP >>will be used to calculate energy, force and stress of the reference >>configurations with atoms up to 150. The total computational time using >>DFT will be 150000 CPU-hours. >>To model different configurations of Xe gas bubbles in U-Mo alloys, a >>120Ã—120Ã—120 cell (40nmÃ—40nmÃ—40nm) based on bcc structure will be >>constructed. About 3.5 million atoms will be introduced in the simulation >>box, which allows adding up to 110 gas bubbles with size around 2.5 nm. >>We will compare the energetics of different bubble superlattices, such as >>cubic, fcc, bcc, hcp and disordered bubbles configurations. We will also >>investigate the effect of Mo concentration on the retention of Xe atoms >>in the lattice. Two different alloys, i.e., U-7wt%Mo and U-10wt%Mo, will >>be studied and be compared to pure bcc Mo and U cases. Meanwhile, >>temperature plays an important role in governing the fluxes of vacancies, >>interstitials and gas atoms to or away from the bubble surface. The >>interested temperature range is between 300 K and 1000 K. In experiment, >>it was observed that the gas bubble superlattice collapses at high >>fission density. A major effect of fission on the microstructure >> is creating a large amount of Frenkel pair defects in the lattice. >>Vacancy can provide efficient diffusion channels for Xe atoms. In this >>work, we will investigate the effect of five parameters (Xe >>concentration, Xe bubble configuration, Mo concentration, temperature, >>and Frenkel pair concentration) on the stability of gas bubble >>superlattices introduced in U-xMo alloys. By systematic analysis of the >>bubble superlatticeâ€™s microstructure and their energetics, we will be >>able to correlate the key parameters to the formation of bubble >>superlattice, and provide a potential mechanism of its formation in U-Mo. >>Combining all the parameters, we will expect about 50 production jobs. >>Our initial test shows that a single MD simulation for 1 nano-second >>takes more than 12000 CPU-hours (256 CPUÃ—24 hours). We therefore request >>the total computational time of 750000 CPU-hours. >> >> Industry partnership: >> Project URL: >> Requested allocation: 750000 >> Q1: 0 >> Q2: 0 >> Q3: 0 >> Q4: 750000 >> Justification: The main calculations are performed by high >>efficient molecular dynamics code LAMMPS. The parallel efficiency test >>for this code shows that it can be well scaled to up to tens of thousands >>of CPUs. Other DFT calculations will be performed by VASP, which is one >>of the widely used DFT code. >> Storage requirements: 1 TB >> >> >>The requester has used undetermined amount hours of their initial startup >>project. >> >>In addition to approving an initial amount, please specify a Category >>and Subcategory for this project. For a list of the current selection >>of approved categories, please see: >> >> https://wiki.lcrc.anl.gov/wiki/Processes/Categories >> >>Once the Allocation committee has approved the project, please go to >>the Project Management page to create it: >> >>https://accounts.lcrc.anl.gov/projects.php >> >>Thank You, >>The LCRC Accounts System > >_______________________________________________ >allocations-admins mailing list >allocations-admins(a)lcrc.anl.gov >https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins

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Re: [allocations-admins] [LCRC Accounts] Project Request: Bubble_superlattice
by Low, John J. 04 Sep '15

04 Sep '15

No. The “project” I am working on is focused on bubbles in oxides and I am doing this with Alejandro Lopez Bezanilla and Laura Ratcliff. John J. Low Principal Computational Science Specialist Computing, Environment and Life Sciences Building 240, 2143 9700 South Cass Avenue Argonne National Laboratory Argonne, IL 60439. 630-252-0045 www.linkedin.com/pub/john-low/15/8b0/5aa/ -----Original Message----- From: <allocations-admins-bounces(a)lcrc.anl.gov> on behalf of "Bair, Raymond A." <rbair(a)anl.gov> Reply-To: LCRC Allocations Admins <allocations-admins(a)lcrc.anl.gov> Date: Friday, September 4, 2015 at 12:03 PM To: LCRC Allocations Admins <allocations-admins(a)lcrc.anl.gov> Subject: Re: [allocations-admins] [LCRC Accounts] Project Request: Bubble_superlattice >This looks fine to me, to start on Blues. > >John low - are you part of this project effort? > >Ray > > > >On 9/4/15, 8:37 AM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of >accounts(a)lcrc.anl.gov" <allocations-admins-bounces(a)lcrc.anl.gov on behalf >of accounts(a)lcrc.anl.gov> wrote: > >>Hello, >> >>A new project on the LCRC cluster has been requested. Please forward >>the information on to the LCRC Allocation sub-committee. >> >> Applicant's name: Zhigang Mei >>Applicant's institution: ANL >> Applicant's division: NE >> Project Name: Bubble_superlattice >> Project title: Atomistic Simulation of Fission Gas Bubble >>Superlattice in Irradiated Materials >> Associated funding: NNSA >> Other Systems: Carbon at CNM >> Science: The accumulation of gaseous species in nuclear >>fuel leads to deleterious microstructural changes that are of utmost >>concern to both fission reactor applications [Trinkaus, J. Nucl. Mater. >>323 (2003) 229]. Inert gas elements â€“ such as helium, xenon and krypton >>- are generated due to fission reactions in nuclear fuel. In general, the >>precipitation of gaseous species into gas-filled bubbles leads to >>volumetric swelling in fuels. According to conventional nucleation >>theory, in the early stages of irradiation, gas atoms diffuse throughout >>the crystal and begin to form clusters due to their insolubility in the >>solid. This clustering can initiate either by chance encounters of the >>wandering gas atoms, or by gas-atom trapping at microstructural >>segregation sites such as grain boundaries (GBs) [Rest, J. Nucl. Mater. >>207 (1993) 192]. The subsequent growth or shrinkage of a gas bubble is >>governed by the fluxes of vacancies, interstitials, and gas atoms to or >> away from the bubble surface. If gas bubbles are located on sinks (such >>as GBs), they may grow indefinitely to the point of interconnection, thus >>lead to rapid fission gas release to the exterior of fuel. It is found >>that the formation of micro-sized fission-gas bubbles at GBs is the major >>reason leading to the fuel swellings at high fission density, while >>nano-sized intragranular gas bubbles have negligible contribution to the >>overall fuel swelling. Therefore a major task for fuel development is to >>control the fission gas bubble microstructures and to retain more >>fission-gas bubble inside fuel grains at high fission density. Some of >>the proposed approaches include (i) Enhancing the solubility of fission >>gas in fuel by modifying the fuel composition and (ii) Increasing the >>grain size in the fuel by heat treatment. So far, these approaches have >>not been well tested and their effects on the nucleation and growth of >>fission gas bubbles are not clear. >>Recent experiments by Gan et al show that fission gas bubbles form fcc >>superlattice in the irradiated bcc U-7Mo dispersion fuel [Miller et al., >>J. Nucl. Mater. 458 (2015) 115]. Typical bubble size and spacing in these >>bubble superlattices are in the range of 2.75-4.5 nm and 10-12 nm, >>respectively. Although ordered bubble superlattice has also been seen in >>ion-irradiated materials, common observations show that superlattice will >>primarily form in the same structure and crystal orientation as the host >>material. Meanwhile the formation of bubble superlattice is >>counterintuitive to the fact that fission gas is randomly generated in >>lattice and gas bubbles should be nucleated in a random manner initially. >>Our own TEM characterization of Xe irradiated U-Mo however shows that gas >>bubbles were randomly distributed in grain instead of forming ordered >>superlattice. >>The goal of this proposal is to investigate the potential mechanisms of >>the formation and collapse of the Xe bubble superlattice in irradiated >>U-Mo alloys using atomistic simulations. We hope this study will provide >>a microscopic model of the nucleation and growth of gas bubble inside >>fuel grains and therefore better control of gas bubble microstructure >>under radiation. >> >> Project description: We will use molecular dynamics (MD) to >>investigate the potential mechanism of the formation of Xe bubbles >>superlattice in U-Mo alloys. The obtained simulation results will be >>compared to the microstructure characterized by TEM in irradiated U-7Mo >>fuels. A ternary U-Mo-Xe potential has been previously developed by >>Smirnova based on embedded atom method (EAM) [Smirnova et al. Modelling >>Simul. Mater. Sci. Eng. 21 (2013) 035011]. However our test shows that >>this potential cannot predict the accurate formation energy of Xe defects >>in U-Mo. Therefore, we will use the so-called force matching method as >>implemented in potfit [Brommer, Modelling Simul Mater Sci Eng 15 (2007) >>295] to develop a new potential for U-Mo-Xe based modified EAM (MEAM). To >>build a potential suitable for the simulation of a complicated ternary >>system, we have to prepare an extensive set of reference configurations >>representing all kinds of possible structures. Each configuration is cor >> responding to one of the possible states of the U-Mo-Xe system. VASP >>will be used to calculate energy, force and stress of the reference >>configurations with atoms up to 150. The total computational time using >>DFT will be 150000 CPU-hours. >>To model different configurations of Xe gas bubbles in U-Mo alloys, a >>120Ã—120Ã—120 cell (40nmÃ—40nmÃ—40nm) based on bcc structure will be >>constructed. About 3.5 million atoms will be introduced in the simulation >>box, which allows adding up to 110 gas bubbles with size around 2.5 nm. >>We will compare the energetics of different bubble superlattices, such as >>cubic, fcc, bcc, hcp and disordered bubbles configurations. We will also >>investigate the effect of Mo concentration on the retention of Xe atoms >>in the lattice. Two different alloys, i.e., U-7wt%Mo and U-10wt%Mo, will >>be studied and be compared to pure bcc Mo and U cases. Meanwhile, >>temperature plays an important role in governing the fluxes of vacancies, >>interstitials and gas atoms to or away from the bubble surface. The >>interested temperature range is between 300 K and 1000 K. In experiment, >>it was observed that the gas bubble superlattice collapses at high >>fission density. A major effect of fission on the microstructure >> is creating a large amount of Frenkel pair defects in the lattice. >>Vacancy can provide efficient diffusion channels for Xe atoms. In this >>work, we will investigate the effect of five parameters (Xe >>concentration, Xe bubble configuration, Mo concentration, temperature, >>and Frenkel pair concentration) on the stability of gas bubble >>superlattices introduced in U-xMo alloys. By systematic analysis of the >>bubble superlatticeâ€™s microstructure and their energetics, we will be >>able to correlate the key parameters to the formation of bubble >>superlattice, and provide a potential mechanism of its formation in U-Mo. >>Combining all the parameters, we will expect about 50 production jobs. >>Our initial test shows that a single MD simulation for 1 nano-second >>takes more than 12000 CPU-hours (256 CPUÃ—24 hours). We therefore request >>the total computational time of 750000 CPU-hours. >> >> Industry partnership: >> Project URL: >> Requested allocation: 750000 >> Q1: 0 >> Q2: 0 >> Q3: 0 >> Q4: 750000 >> Justification: The main calculations are performed by high >>efficient molecular dynamics code LAMMPS. The parallel efficiency test >>for this code shows that it can be well scaled to up to tens of thousands >>of CPUs. Other DFT calculations will be performed by VASP, which is one >>of the widely used DFT code. >> Storage requirements: 1 TB >> >> >>The requester has used undetermined amount hours of their initial startup >>project. >> >>In addition to approving an initial amount, please specify a Category >>and Subcategory for this project. For a list of the current selection >>of approved categories, please see: >> >> https://wiki.lcrc.anl.gov/wiki/Processes/Categories >> >>Once the Allocation committee has approved the project, please go to >>the Project Management page to create it: >> >>https://accounts.lcrc.anl.gov/projects.php >> >>Thank You, >>The LCRC Accounts System > >_______________________________________________ >allocations-admins mailing list >allocations-admins(a)lcrc.anl.gov >https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins

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Re: [allocations-admins] [LCRC Accounts] Project Request: Bubble_superlattice
by Bair, Raymond A. 04 Sep '15

04 Sep '15

This looks fine to me, to start on Blues. John low - are you part of this project effort? Ray On 9/4/15, 8:37 AM, "allocations-admins-bounces(a)lcrc.anl.gov on behalf of accounts(a)lcrc.anl.gov" <allocations-admins-bounces(a)lcrc.anl.gov on behalf of accounts(a)lcrc.anl.gov> wrote: >Hello, > >A new project on the LCRC cluster has been requested. Please forward >the information on to the LCRC Allocation sub-committee. > > Applicant's name: Zhigang Mei >Applicant's institution: ANL > Applicant's division: NE > Project Name: Bubble_superlattice > Project title: Atomistic Simulation of Fission Gas Bubble >Superlattice in Irradiated Materials > Associated funding: NNSA > Other Systems: Carbon at CNM > Science: The accumulation of gaseous species in nuclear >fuel leads to deleterious microstructural changes that are of utmost >concern to both fission reactor applications [Trinkaus, J. Nucl. Mater. >323 (2003) 229]. Inert gas elements â€“ such as helium, xenon and krypton >- are generated due to fission reactions in nuclear fuel. In general, the >precipitation of gaseous species into gas-filled bubbles leads to >volumetric swelling in fuels. According to conventional nucleation >theory, in the early stages of irradiation, gas atoms diffuse throughout >the crystal and begin to form clusters due to their insolubility in the >solid. This clustering can initiate either by chance encounters of the >wandering gas atoms, or by gas-atom trapping at microstructural >segregation sites such as grain boundaries (GBs) [Rest, J. Nucl. Mater. >207 (1993) 192]. The subsequent growth or shrinkage of a gas bubble is >governed by the fluxes of vacancies, interstitials, and gas atoms to or > away from the bubble surface. If gas bubbles are located on sinks (such >as GBs), they may grow indefinitely to the point of interconnection, thus >lead to rapid fission gas release to the exterior of fuel. It is found >that the formation of micro-sized fission-gas bubbles at GBs is the major >reason leading to the fuel swellings at high fission density, while >nano-sized intragranular gas bubbles have negligible contribution to the >overall fuel swelling. Therefore a major task for fuel development is to >control the fission gas bubble microstructures and to retain more >fission-gas bubble inside fuel grains at high fission density. Some of >the proposed approaches include (i) Enhancing the solubility of fission >gas in fuel by modifying the fuel composition and (ii) Increasing the >grain size in the fuel by heat treatment. So far, these approaches have >not been well tested and their effects on the nucleation and growth of >fission gas bubbles are not clear. >Recent experiments by Gan et al show that fission gas bubbles form fcc >superlattice in the irradiated bcc U-7Mo dispersion fuel [Miller et al., >J. Nucl. Mater. 458 (2015) 115]. Typical bubble size and spacing in these >bubble superlattices are in the range of 2.75-4.5 nm and 10-12 nm, >respectively. Although ordered bubble superlattice has also been seen in >ion-irradiated materials, common observations show that superlattice will >primarily form in the same structure and crystal orientation as the host >material. Meanwhile the formation of bubble superlattice is >counterintuitive to the fact that fission gas is randomly generated in >lattice and gas bubbles should be nucleated in a random manner initially. >Our own TEM characterization of Xe irradiated U-Mo however shows that gas >bubbles were randomly distributed in grain instead of forming ordered >superlattice. >The goal of this proposal is to investigate the potential mechanisms of >the formation and collapse of the Xe bubble superlattice in irradiated >U-Mo alloys using atomistic simulations. We hope this study will provide >a microscopic model of the nucleation and growth of gas bubble inside >fuel grains and therefore better control of gas bubble microstructure >under radiation. > > Project description: We will use molecular dynamics (MD) to >investigate the potential mechanism of the formation of Xe bubbles >superlattice in U-Mo alloys. The obtained simulation results will be >compared to the microstructure characterized by TEM in irradiated U-7Mo >fuels. A ternary U-Mo-Xe potential has been previously developed by >Smirnova based on embedded atom method (EAM) [Smirnova et al. Modelling >Simul. Mater. Sci. Eng. 21 (2013) 035011]. However our test shows that >this potential cannot predict the accurate formation energy of Xe defects >in U-Mo. Therefore, we will use the so-called force matching method as >implemented in potfit [Brommer, Modelling Simul Mater Sci Eng 15 (2007) >295] to develop a new potential for U-Mo-Xe based modified EAM (MEAM). To >build a potential suitable for the simulation of a complicated ternary >system, we have to prepare an extensive set of reference configurations >representing all kinds of possible structures. Each configuration is cor > responding to one of the possible states of the U-Mo-Xe system. VASP >will be used to calculate energy, force and stress of the reference >configurations with atoms up to 150. The total computational time using >DFT will be 150000 CPU-hours. >To model different configurations of Xe gas bubbles in U-Mo alloys, a >120Ã—120Ã—120 cell (40nmÃ—40nmÃ—40nm) based on bcc structure will be >constructed. About 3.5 million atoms will be introduced in the simulation >box, which allows adding up to 110 gas bubbles with size around 2.5 nm. >We will compare the energetics of different bubble superlattices, such as >cubic, fcc, bcc, hcp and disordered bubbles configurations. We will also >investigate the effect of Mo concentration on the retention of Xe atoms >in the lattice. Two different alloys, i.e., U-7wt%Mo and U-10wt%Mo, will >be studied and be compared to pure bcc Mo and U cases. Meanwhile, >temperature plays an important role in governing the fluxes of vacancies, >interstitials and gas atoms to or away from the bubble surface. The >interested temperature range is between 300 K and 1000 K. In experiment, >it was observed that the gas bubble superlattice collapses at high >fission density. A major effect of fission on the microstructure > is creating a large amount of Frenkel pair defects in the lattice. >Vacancy can provide efficient diffusion channels for Xe atoms. In this >work, we will investigate the effect of five parameters (Xe >concentration, Xe bubble configuration, Mo concentration, temperature, >and Frenkel pair concentration) on the stability of gas bubble >superlattices introduced in U-xMo alloys. By systematic analysis of the >bubble superlatticeâ€™s microstructure and their energetics, we will be >able to correlate the key parameters to the formation of bubble >superlattice, and provide a potential mechanism of its formation in U-Mo. >Combining all the parameters, we will expect about 50 production jobs. >Our initial test shows that a single MD simulation for 1 nano-second >takes more than 12000 CPU-hours (256 CPUÃ—24 hours). We therefore request >the total computational time of 750000 CPU-hours. > > Industry partnership: > Project URL: > Requested allocation: 750000 > Q1: 0 > Q2: 0 > Q3: 0 > Q4: 750000 > Justification: The main calculations are performed by high >efficient molecular dynamics code LAMMPS. The parallel efficiency test >for this code shows that it can be well scaled to up to tens of thousands >of CPUs. Other DFT calculations will be performed by VASP, which is one >of the widely used DFT code. > Storage requirements: 1 TB > > >The requester has used undetermined amount hours of their initial startup >project. > >In addition to approving an initial amount, please specify a Category >and Subcategory for this project. For a list of the current selection >of approved categories, please see: > > https://wiki.lcrc.anl.gov/wiki/Processes/Categories > >Once the Allocation committee has approved the project, please go to >the Project Management page to create it: > >https://accounts.lcrc.anl.gov/projects.php > >Thank You, >The LCRC Accounts System

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[LCRC Accounts] Project Request: CEES-II-Wolverton
by accounts＠lcrc.anl.gov 04 Sep '15

04 Sep '15

Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: Chris Wolverton Applicant's institution: ANL Applicant's division: Computing, Environment, and Life Sciences Project Name: CEES-II-Wolverton Project title: DFT Computation of Hybrid and Li-ion Battery Materials Associated funding: CEES-II EFRC Other Systems: Science: Recent experiments have shown that lithium and oxygen can be electrochemically removed from Li5FeO4 (5Li2O·Fe2O3) and re-accommodated during discharge, creating the possibility of its use as a high-capacity electrode in a hybrid Li-ion/Li–O2 electrochemical cell. Taking this novel chemistry as a model, we use density functional theory (DFT) within a high-throughput framework to screen for analogous reactions in other materials. We also are interested in determining the mass tranport kinetics of the phase transformations in these materials. Project description: 1. Thermodynamics studies including electronic structure calculations, phase transformation calculations for new Li-ion and hybrid Li-ion/Li-O2 battery chemistries. 2. Kinetics studies including defect formation energy calculations, ab-initio molecular dynamics, nudged elastic band calculations and kinetic Monte Carlo simulations for Li/O transport in hybrid materials including Li-Fe-O and Li-Mn-O. 3. New high-throughput DFT discovery of novel hybrid Metal-ion/Metal-O2 battery chemistries, novel battery anode/cathode materials. 4. Structure predictions of new phases observed in the charging/discharging of transition metal oxides. Computational methods employed will largely be DFT-based, multiprocessor jobs. Industry partnership: Project URL: Requested allocation: 500000 Q1: 0 Q2: 0 Q3: 0 Q4: 500000 Justification: Our group has considerable experience with high-throughput DFT computation, and have demonstrated this in the Open Quantum Materials Database (OQMD). OQMD is available online at oqmd.org, and consists of a database of >300,000 DFT calculations of known and hypothetical inorganic materials. Storage requirements: The requester has used undetermined amount hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System

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[LCRC Accounts] Project Request: Bubble_superlattice
by accounts＠lcrc.anl.gov 04 Sep '15

04 Sep '15

Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: Zhigang Mei Applicant's institution: ANL Applicant's division: NE Project Name: Bubble_superlattice Project title: Atomistic Simulation of Fission Gas Bubble Superlattice in Irradiated Materials Associated funding: NNSA Other Systems: Carbon at CNM Science: The accumulation of gaseous species in nuclear fuel leads to deleterious microstructural changes that are of utmost concern to both fission reactor applications [Trinkaus, J. Nucl. Mater. 323 (2003) 229]. Inert gas elements – such as helium, xenon and krypton - are generated due to fission reactions in nuclear fuel. In general, the precipitation of gaseous species into gas-filled bubbles leads to volumetric swelling in fuels. According to conventional nucleation theory, in the early stages of irradiation, gas atoms diffuse throughout the crystal and begin to form clusters due to their insolubility in the solid. This clustering can initiate either by chance encounters of the wandering gas atoms, or by gas-atom trapping at microstructural segregation sites such as grain boundaries (GBs) [Rest, J. Nucl. Mater. 207 (1993) 192]. The subsequent growth or shrinkage of a gas bubble is governed by the fluxes of vacancies, interstitials, and gas atoms to or away from the bubble surface. If gas bubbles are located on sinks (such as GBs), they may grow indefinitely to the point of interconnection, thus lead to rapid fission gas release to the exterior of fuel. It is found that the formation of micro-sized fission-gas bubbles at GBs is the major reason leading to the fuel swellings at high fission density, while nano-sized intragranular gas bubbles have negligible contribution to the overall fuel swelling. Therefore a major task for fuel development is to control the fission gas bubble microstructures and to retain more fission-gas bubble inside fuel grains at high fission density. Some of the proposed approaches include (i) Enhancing the solubility of fission gas in fuel by modifying the fuel composition and (ii) Increasing the grain size in the fuel by heat treatment. So far, these approaches have not been well tested and their effects on the nucleation and growth of fission gas bubbles are not clear. Recent experiments by Gan et al show that fission gas bubbles form fcc superlattice in the irradiated bcc U-7Mo dispersion fuel [Miller et al., J. Nucl. Mater. 458 (2015) 115]. Typical bubble size and spacing in these bubble superlattices are in the range of 2.75-4.5 nm and 10-12 nm, respectively. Although ordered bubble superlattice has also been seen in ion-irradiated materials, common observations show that superlattice will primarily form in the same structure and crystal orientation as the host material. Meanwhile the formation of bubble superlattice is counterintuitive to the fact that fission gas is randomly generated in lattice and gas bubbles should be nucleated in a random manner initially. Our own TEM characterization of Xe irradiated U-Mo however shows that gas bubbles were randomly distributed in grain instead of forming ordered superlattice. The goal of this proposal is to investigate the potential mechanisms of the formation and collapse of the Xe bubble superlattice in irradiated U-Mo alloys using atomistic simulations. We hope this study will provide a microscopic model of the nucleation and growth of gas bubble inside fuel grains and therefore better control of gas bubble microstructure under radiation. Project description: We will use molecular dynamics (MD) to investigate the potential mechanism of the formation of Xe bubbles superlattice in U-Mo alloys. The obtained simulation results will be compared to the microstructure characterized by TEM in irradiated U-7Mo fuels. A ternary U-Mo-Xe potential has been previously developed by Smirnova based on embedded atom method (EAM) [Smirnova et al. Modelling Simul. Mater. Sci. Eng. 21 (2013) 035011]. However our test shows that this potential cannot predict the accurate formation energy of Xe defects in U-Mo. Therefore, we will use the so-called force matching method as implemented in potfit [Brommer, Modelling Simul Mater Sci Eng 15 (2007) 295] to develop a new potential for U-Mo-Xe based modified EAM (MEAM). To build a potential suitable for the simulation of a complicated ternary system, we have to prepare an extensive set of reference configurations representing all kinds of possible structures. Each configuration is cor responding to one of the possible states of the U-Mo-Xe system. VASP will be used to calculate energy, force and stress of the reference configurations with atoms up to 150. The total computational time using DFT will be 150000 CPU-hours. To model different configurations of Xe gas bubbles in U-Mo alloys, a 120×120×120 cell (40nm×40nm×40nm) based on bcc structure will be constructed. About 3.5 million atoms will be introduced in the simulation box, which allows adding up to 110 gas bubbles with size around 2.5 nm. We will compare the energetics of different bubble superlattices, such as cubic, fcc, bcc, hcp and disordered bubbles configurations. We will also investigate the effect of Mo concentration on the retention of Xe atoms in the lattice. Two different alloys, i.e., U-7wt%Mo and U-10wt%Mo, will be studied and be compared to pure bcc Mo and U cases. Meanwhile, temperature plays an important role in governing the fluxes of vacancies, interstitials and gas atoms to or away from the bubble surface. The interested temperature range is between 300 K and 1000 K. In experiment, it was observed that the gas bubble superlattice collapses at high fission density. A major effect of fission on the microstructure is creating a large amount of Frenkel pair defects in the lattice. Vacancy can provide efficient diffusion channels for Xe atoms. In this work, we will investigate the effect of five parameters (Xe concentration, Xe bubble configuration, Mo concentration, temperature, and Frenkel pair concentration) on the stability of gas bubble superlattices introduced in U-xMo alloys. By systematic analysis of the bubble superlattice’s microstructure and their energetics, we will be able to correlate the key parameters to the formation of bubble superlattice, and provide a potential mechanism of its formation in U-Mo. Combining all the parameters, we will expect about 50 production jobs. Our initial test shows that a single MD simulation for 1 nano-second takes more than 12000 CPU-hours (256 CPU×24 hours). We therefore request the total computational time of 750000 CPU-hours. Industry partnership: Project URL: Requested allocation: 750000 Q1: 0 Q2: 0 Q3: 0 Q4: 750000 Justification: The main calculations are performed by high efficient molecular dynamics code LAMMPS. The parallel efficiency test for this code shows that it can be well scaled to up to tens of thousands of CPUs. Other DFT calculations will be performed by VASP, which is one of the widely used DFT code. Storage requirements: 1 TB The requester has used undetermined amount hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System

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New LCRC report submitted for gcmat
by support＠lcrc.anl.gov 03 Sep '15

03 Sep '15

Full project report at https://accounts.lcrc.anl.gov/reporting/project/2015/?project=gcmat

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Re: [allocations-admins] [lcrc-support #274209] Core hours
by Bair, Raymond A. 03 Sep '15

03 Sep '15

We approve this request. ----------------------------------------- Ray Bair Computing, Environment, and Life Sciences Argonne National Laboratory and the University of Chicago TCS Building 240, Room 4122 9700 South Cass Avenue Argonne, IL 60439 email: rbair(at)anl.gov Phone: (630)252-5751 On 9/2/15, 3:29 PM, "Som, Sibendu" <ssom(a)anl.gov> wrote: >Dear All: > >Our projects are running low on core hours. We have couple of paper >deadlines on October 15th with our industrial partners. Will it be >possible to add core hours to the following projects? >dual-fuel-sprays >gm_gasexchange >Denso_simulations > >Adding 100K on each of them will suffice. I understand that these many >core hours may not be remaining. Whatever you could add on each of the >projects will be very helpful. Please let me know asap. > >Thanks, >Sibendu >

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