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

Re: [allocations-admins] [LCRC Accounts] Project Request: AlN
by John Valdes 18 Feb '15

18 Feb '15

50K for this quarter POC: Larry Curtiss pri: 1 Cat: P:Nano On Mon, Feb 16, 2015 at 06:22:30PM -0600, 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: Anh Ngo > Applicant's institution: ANL > Applicant's division: MSD > Project Name: AlN > Project title: A DFT study of reaction pathways of NH3 decomposition on AlN (0001) surface > Associated funding: Strategic LDRD > Other Systems: > Science: Strong demands for high-efficiency light-emitting diodes in the deep-ultraviolet and sensors have led to renewed interest in the growth of high-quality AlN. However, the growth of high quality AlN is extremely difficult due to the weak surface migration of Al adatoms. The most commonly used growth technique for AlN films is metalorganic chemical vapor deposition (MOCVD) with ammonia serving NH3 as the nitrogen precursor. Identification of kinetic pathways that produce high nitrogen activity during precursor surface decomposition and Al precursor migration pathways are essential to understanding and optimizing growth of metastable nitrides such as AlN using reactive vapors. > In this study, we plan to further address these proposed determining factors to catalytic activity by calculating reaction thermodynamics and kinetics of the decomposition of NH3 on the technologically relevant (0001) surface of AlN via H dissociation as well as a new pathway involving H transfer between the reduced NHx (x = 1???2) species on the surface. We will also investigate decomposition and migration of Al precursors. These studies will provide valuable information toward rational designs of catalysts with high activity and selectivity for the growth of high-quality AlN under MOCVD conditions. This work will help interpretation of in-situ x-ray experiments on AlN growth at the APS. > > Project description: Structure optimizations of the adsorbate-free (0001) surface of AlN were already investigated using (2 ?? 2) surface unit cells. We will perform density functional theory (DFT) calculations to determine structure, bonding, and reaction energies of the adsorbed species. Periodic boundary condition (PBC) will be imposed in order to maintain periodicity of the solid support. Gradient corrected PBE density functional will be used for these calculations. The Climbing Nudged Elastic Band (cNEB) method of Henkelman and coworkers will be used to calculate transition states and activation barriers for formation of different surface species. > Each structure in the supported (0001) surface of AlN typically involves ~100 atoms. To obtain accurate reaction energies and barriers, rigorous density functional theory (DFT) calculations are needed. We intend to carry out the DFT calculations using the VASP package. VASP is currently available on Blues cluster and scaling with number of processors is well established. For the MPI version of VASP with the system size of ~100 atoms, a good performance was observed up to 32 processors. > Energy optimization in VASP takes approximately 750 CPU hours and we plan approximately 100 of such calculations for different adsorbate geometries. The Climbing Nudged Elastic Band (cNEB) calculation (with 5 to 7 images) takes approximately 1600 CPU hours and we plan to run 60 of these calculations to find reaction pathways. > So our total request is 750*150 + 60*1600 = 208,500 core hours > > Industry partnership: none > Project URL: > Requested allocation: 208500 > Q1: 0 > Q2: 50000 > Q3: 80000 > Q4: 78500 > Justification: > Storage requirements: no additional storage needed > > > 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 Allocation Request
by John Valdes 18 Feb '15

18 Feb '15

100K for rest of year On Mon, Feb 16, 2015 at 03:34:40PM -0600, accounts(a)lcrc.anl.gov wrote: > Hello, > > A change in allocation has been requested: > > Requester: dford (Denise Ford) > Project: SRF-materials > Title: Modeling of Impurity Structures in Niobium Superconducting Radio-Frequency Cavities > Description: This phase of the project will focus on surface and interface properties. We are particularly interested in the change in superconducting properties at surfaces and across the interfaces between the host niobium and impurity phase precipitates. Since the lattices of the precipitates and the host niobium metal may deform considerably near the interfaces, we will consider bulk models of precipitates and the niobium under strain, as well as full interface models. The models will consist of up ~100 atoms. Density functional theory in VASP will be used to optimize the geometries of the models and calculate their electronic properties. Phonon DOS and dispersions will be evaluated using Phonopy, which uses the force constants calculated for atomic perturbations via density functional theory in VASP. Since defects, including interfaces, reduce the symmetry of the systems, many perturbations will need to be performed for some of these models to accurately assess > the phonon properties. Abinit will also be used to calculate the superconducting properties (electron-phonon coupling and transition temperature) of select structures. Accurate determination of the electron-phonon coupling is very computationally demanding, requiring dense k-point and q-point grids. Abinit parallelizes over k-points, bands, and perturbations; so it is particularly suitable for use on large machines with many cores. > Current: undetermined amount > Justification: > > Requested: 150000 > > A specific reason has been given: > I need to complete a few more DFPT calculations with Abinit, which works very well on Blues. The extra time will be very helpful to this project. > > This needs to be approved and the final allocation amount decided upon. > > 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 Allocation Request
by John Valdes 18 Feb '15

18 Feb '15

150K for current quarter On Mon, Feb 16, 2015 at 11:39:49AM -0600, accounts(a)lcrc.anl.gov wrote: > Hello, > > A change in allocation has been requested: > > Requester: sunhwan (Sunhwan Jo) > Project: entropy > Title: Quantifying protein-protein binding with greatly scalable multiple copy algorithms of NAMD > Description: In PMF-based framework, a set of geometric and conformational restraints is applied to the proteins to reduce sampling noise and accelerate the convergence of the resulting free energy profile. These biases are rigorously accounted for to produce the absolute binding free energy. To enhance the PMF convergence, we will combine the umbrella sampling with Hamiltonian and temperature (??? and T) replica-exchange molecular dynamics (REM) algorithm. In the US/(???,T)-REMD simulation approach, multiple copies of the molecular ???systems are simulated concurrently, but??? all with different??? conditions, e.g., umbrella potential (Hamiltonians) or temperature. Attempts are periodically made to exchange configurations between different systems using a Metropolis-type Monte Carlo acceptance criterion, insuring Boltzmann-weighted statistics. Such REMD??? methodology is extremely scalable, yet also very effective to sample a rugged free energy surface. > > We anticipate the simulation systems will be comprised of ~50,000 atoms and using at least 255 replicas concurrently. Because of its large size, we plan to use primarily Mira for production and Fusion will be used for initial system preparation and development of enhanced methodology in PMF-based framework. All planned simulations will be carried out by the open-source NAMD molecular dynamics software. The software engine used for the planned simulations is NAMD 2.10 with Charm++ 6.4.0. We have tested t he performance on BG/Q Mira. The scaling of parallel performance was linear up to 512 cores for our test system comprised of 100,000 atoms without using restraint potential and achieved the speed of about 0.025 s/step. Using restraint potential reduces the parallel performance significantly (~0.2 s/step). > > The expected number of project member is 3. I, Sunhwan Jo, recently joined LCF as a postdoctoral appointee and will be the main person performing code improvement and algorithm development under the supervision of Wei Jiang (LCF) and Benoit Roux (UChicago). > > > Current: undetermined amount > Justification: > > Requested: 200000 > > A specific reason has been given: > We are testing entropy estimation method with a newly developed solute tempering methodology. > > This needs to be approved and the final allocation amount decided upon. > > 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 Allocation Request
by John Valdes 18 Feb '15

18 Feb '15

Ok for 100K, rest of the FY On Mon, Feb 16, 2015 at 11:31:18AM -0600, accounts(a)lcrc.anl.gov wrote: > Hello, > > A change in allocation has been requested: > > Requester: verdicm (Marco Verdicchio) > Project: LowF_VRC-TST > Title: Low frequencies modes coupling in Variable Reaction Coordinate TST > Description: - Computational methods: > > We intend to use VRC-TST theory to study the effect of coupled low frequencies motions on EJ-resolved, microcanonical and canonical kinetic constants for several radical-radical association reactions. The central focus of VRC-TST is the evaluation of the reactive flux through an arbitrary dividing surface for several temperatures. In particular a multifaceted dividing surface approach, which allow for the incorporation of multiple dividing surfaces for each binding site, will be adopted. This scheme allows high flexibility on the dividing surface shape and the possibility to take into account additional reaction pathways (i.e. H atom abstraction). Unfortunately the computational cost of each kinetic calculation increases with the number of considered dividing surfaces. A variational minimization of the reactive flux is then performed with respect to both the location of the pivot points and the distances between them. > > > The previous allocation let us to investigate the low-frequencies effect on the rate constants for several systems: > > - CH3 + H > - CH3 + CH3 > - CH2CH3 + H > - CH2CH3 + CH3 > - H + CH2OH > > with excellent results. > > The Blues machine has been found to be of great help for this type of studies allowing us to use a large number of processors (128 cpu for an average of 24h per job) and speed up considerably our calculations. > > In this second stage of the project, we would like to move our attention to different systems like: > - CH3 + CH2OH > - H + CH2OH > These systems, in fact, have been already investigated within the previous allocation, but the complexity of their potential energy surface require additional work in order to work out an accurate rate constant (the low-freq effect has a strong dependence on the potential energy surface). > Moreover the extension of this method to oxygenated systems: > - O2 + CH3 > - O2 + CH2CH3 > requires the use of high level ab initio calculations (because of the presence of the O2 molecule) which are highly computationally demanding. > > - Technical details: > > Kinetic calculations will be performed using the VRC-TST method as implemented in the computer code VaReCoF (Y. Georgievskii, S.J. Klippenstein, VaReCoF, Sandia National Laboratories and Argonne National Laboratory, 2006). > The code makes use of the MOLPRO or GAUSSIAN quantum chemistry software for on-the-fly evaluation of the potential energy. > A Python interface to the code has been implemented for the management of the input files (reference energy evaluation, pivot points positions, etc.), for the generation of the input different structures ([Phi,Chi] grid of points) and for results post processing. > > The code does not require large amount of memory (less than 1GB) and works very efficiently on parallel architectures. The code makes use of MPI and shows a speed-up efficiency of about 60% for up to 96 CPU???s (test performed on a 8 cpu/cores AMD Operton 2354 machine). Improvement is expected with better CPUs and fastest internode connections. > > > - Expected number of project members: 3 > > Current: undetermined amount > Justification: > > Requested: 100000 > > A specific reason has been given: > Additional calculations are required in order to confirm the fitting procedure we are developing. > > This needs to be approved and the final allocation amount decided upon. > > 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 Allocation Request
by John Valdes 18 Feb '15

18 Feb '15

Ok for 150K John On Fri, Feb 13, 2015 at 08:39:29AM -0600, accounts(a)lcrc.anl.gov wrote: > Hello, > > A change in allocation has been requested: > > Requester: ssom (Sibendu Som) > Project: spray-modeling > Title: Development of a near nozzle spray modeling approach > Description: The project is divided into 5 major tasks to be performed in 3 years in collaboration with Convergent Science Inc.: > Task 1: Development and validation of a nozzle flow model to account of transient effects such as needle movement, needle off-axis motion, rail pressure fluctuations etc. > Task 2: Further advancement of KH-ACT (Kelvin Helmholtz ??? Aerodynamic Cavitation Turbulence) primary breakup model to calculate more accurately relevant length and time-scales for the cavitation, turbulence, and aerodynamically induced breakup processes. > Task 3: In the past nozzle flow and spray simulations have been statically coupled. A dynamic coupling approach will be developed so that the nozzle flow simulations can influence the spray development and vice versa. This is quite complicated since the length and time scales associated with nozzle flow processes are significantly different from spray processes. > Task 4: An one equation non-viscosity dynamic structure model large eddy simulation (LES) based turbulence modeling approach will be implemented in CONVERGE. Grid-convergence on critical spray parameters will be evaluated with the implemented LES models. > Task 5: Implementation of an Eulerian-Lagrangian spray model: While dynamic coupling of the nozzle flow and KH-ACT models will enhance the accuracy of spray simulations, a transition between the Eulerian and Lagrangian phases must take place at the nozzle exit with this approach. Moving the transition point downstream allows for a more natural bridge between the coupled simulations as the liquid fuel is modeled in an Eulerian framework on both sides of the nozzle exit. A specific challenge of this task is developing an algorithm to convert the Eulerian liquid to Lagrangian parcels outside of the dense spray region. > > Current: undetermined amount > Justification: > > Requested: 150000 > > A specific reason has been given: > Several of our large cases crashed as we were developing and testing a new model. More core hours will help us finish our paper deadlines for ILASS and ASME. > > This needs to be approved and the final allocation amount decided upon. > > 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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[LCRC Accounts] Project Request: AlN
by accounts＠lcrc.anl.gov 16 Feb '15

16 Feb '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: Anh Ngo Applicant's institution: ANL Applicant's division: MSD Project Name: AlN Project title: A DFT study of reaction pathways of NH3 decomposition on AlN (0001) surface Associated funding: Strategic LDRD Other Systems: Science: Strong demands for high-efficiency light-emitting diodes in the deep-ultraviolet and sensors have led to renewed interest in the growth of high-quality AlN. However, the growth of high quality AlN is extremely difficult due to the weak surface migration of Al adatoms. The most commonly used growth technique for AlN films is metalorganic chemical vapor deposition (MOCVD) with ammonia serving NH3 as the nitrogen precursor. Identification of kinetic pathways that produce high nitrogen activity during precursor surface decomposition and Al precursor migration pathways are essential to understanding and optimizing growth of metastable nitrides such as AlN using reactive vapors. In this study, we plan to further address these proposed determining factors to catalytic activity by calculating reaction thermodynamics and kinetics of the decomposition of NH3 on the technologically relevant (0001) surface of AlN via H dissociation as well as a new pathway involving H transfer between the reduced NHx (x = 1–2) species on the surface. We will also investigate decomposition and migration of Al precursors. These studies will provide valuable information toward rational designs of catalysts with high activity and selectivity for the growth of high-quality AlN under MOCVD conditions. This work will help interpretation of in-situ x-ray experiments on AlN growth at the APS. Project description: Structure optimizations of the adsorbate-free (0001) surface of AlN were already investigated using (2 × 2) surface unit cells. We will perform density functional theory (DFT) calculations to determine structure, bonding, and reaction energies of the adsorbed species. Periodic boundary condition (PBC) will be imposed in order to maintain periodicity of the solid support. Gradient corrected PBE density functional will be used for these calculations. The Climbing Nudged Elastic Band (cNEB) method of Henkelman and coworkers will be used to calculate transition states and activation barriers for formation of different surface species. Each structure in the supported (0001) surface of AlN typically involves ~100 atoms. To obtain accurate reaction energies and barriers, rigorous density functional theory (DFT) calculations are needed. We intend to carry out the DFT calculations using the VASP package. VASP is currently available on Blues cluster and scaling with number of processors is well established. For the MPI version of VASP with the system size of ~100 atoms, a good performance was observed up to 32 processors. Energy optimization in VASP takes approximately 750 CPU hours and we plan approximately 100 of such calculations for different adsorbate geometries. The Climbing Nudged Elastic Band (cNEB) calculation (with 5 to 7 images) takes approximately 1600 CPU hours and we plan to run 60 of these calculations to find reaction pathways. So our total request is 750*150 + 60*1600 = 208,500 core hours Industry partnership: none Project URL: Requested allocation: 208500 Q1: 0 Q2: 50000 Q3: 80000 Q4: 78500 Justification: Storage requirements: no additional storage needed 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 Allocation Request
by accounts＠lcrc.anl.gov 16 Feb '15

16 Feb '15

Hello, A change in allocation has been requested: Requester: landera (Alexander Landera) Project: udmh_pyrolysis Title: Pyrolysis of UDMH and other propellants Description: The project has as its main goal, the description of long range interactions involved in the pyrolysis of Unsymmetrical Di-methylhydrazine (UDMH), and other similar propellants. Further, as a separate goal, we will also obtain branching ratios for the products formed in these pyrolysis reactions. These propellants are used in the propulsion systems of many rocket systems. It will require the extensive use of the Molpro quantum Mechanical package. Molpro scales well with a small number of processors (16 or less), and for most molpro calculations, this is what we will need. We will also need access to a program called VaReCoF, which allows for the calculation of the flux involved in association reactions. It works by invoking multiple instances of molpro, and the code makes use of MPI and shows a speed-up efficiency of about 60% for up to 96 CPU’s (test performed on a 8 cpu/cores AMD Operton 2354 machine). This provides the efficiency that we need to complete this project successfully. Additionally, these two programs (molpro and VaReCoF) are already installed in both Blues and Fusion. When running VaReCoF, we will be using between 100 and 200 cores at once. The reference for the VaReCoF program is as follows: VaReCoF (Y. Georgievskii, S.J. Klippenstein, VaReCoF, Sandia National Laboratories and Argonne National Laboratory, 2006). Number of project members: 3 Current: undetermined amount Justification: Requested: 100000 A specific reason has been given: My work is going really well running distributed calculations in order to obtain reaction rates for gas kinetics. However, we are getting ready to expand (as noted in the project title) to other propellants, and will need the extra core hours to cover those associated calculations. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System

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[LCRC Accounts] Project Allocation Request
by accounts＠lcrc.anl.gov 16 Feb '15

16 Feb '15

Hello, A change in allocation has been requested: Requester: verdicm (Marco Verdicchio) Project: LowF_VRC-TST Title: Low frequencies modes coupling in Variable Reaction Coordinate TST Description: - Computational methods: We intend to use VRC-TST theory to study the effect of coupled low frequencies motions on EJ-resolved, microcanonical and canonical kinetic constants for several radical-radical association reactions. The central focus of VRC-TST is the evaluation of the reactive flux through an arbitrary dividing surface for several temperatures. In particular a multifaceted dividing surface approach, which allow for the incorporation of multiple dividing surfaces for each binding site, will be adopted. This scheme allows high flexibility on the dividing surface shape and the possibility to take into account additional reaction pathways (i.e. H atom abstraction). Unfortunately the computational cost of each kinetic calculation increases with the number of considered dividing surfaces. A variational minimization of the reactive flux is then performed with respect to both the location of the pivot points and the distances between them. The previous allocation let us to investigate the low-frequencies effect on the rate constants for several systems: - CH3 + H - CH3 + CH3 - CH2CH3 + H - CH2CH3 + CH3 - H + CH2OH with excellent results. The Blues machine has been found to be of great help for this type of studies allowing us to use a large number of processors (128 cpu for an average of 24h per job) and speed up considerably our calculations. In this second stage of the project, we would like to move our attention to different systems like: - CH3 + CH2OH - H + CH2OH These systems, in fact, have been already investigated within the previous allocation, but the complexity of their potential energy surface require additional work in order to work out an accurate rate constant (the low-freq effect has a strong dependence on the potential energy surface). Moreover the extension of this method to oxygenated systems: - O2 + CH3 - O2 + CH2CH3 requires the use of high level ab initio calculations (because of the presence of the O2 molecule) which are highly computationally demanding. - Technical details: Kinetic calculations will be performed using the VRC-TST method as implemented in the computer code VaReCoF (Y. Georgievskii, S.J. Klippenstein, VaReCoF, Sandia National Laboratories and Argonne National Laboratory, 2006). The code makes use of the MOLPRO or GAUSSIAN quantum chemistry software for on-the-fly evaluation of the potential energy. A Python interface to the code has been implemented for the management of the input files (reference energy evaluation, pivot points positions, etc.), for the generation of the input different structures ([Phi,Chi] grid of points) and for results post processing. The code does not require large amount of memory (less than 1GB) and works very efficiently on parallel architectures. The code makes use of MPI and shows a speed-up efficiency of about 60% for up to 96 CPU’s (test performed on a 8 cpu/cores AMD Operton 2354 machine). Improvement is expected with better CPUs and fastest internode connections. - Expected number of project members: 3 Current: undetermined amount Justification: Requested: 100000 A specific reason has been given: Additional calculations are required in order to confirm the fitting procedure we are developing. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System

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[LCRC Accounts] Project Allocation Request
by accounts＠lcrc.anl.gov 16 Feb '15

16 Feb '15

Hello, A change in allocation has been requested: Requester: dford (Denise Ford) Project: SRF-materials Title: Modeling of Impurity Structures in Niobium Superconducting Radio-Frequency Cavities Description: This phase of the project will focus on surface and interface properties. We are particularly interested in the change in superconducting properties at surfaces and across the interfaces between the host niobium and impurity phase precipitates. Since the lattices of the precipitates and the host niobium metal may deform considerably near the interfaces, we will consider bulk models of precipitates and the niobium under strain, as well as full interface models. The models will consist of up ~100 atoms. Density functional theory in VASP will be used to optimize the geometries of the models and calculate their electronic properties. Phonon DOS and dispersions will be evaluated using Phonopy, which uses the force constants calculated for atomic perturbations via density functional theory in VASP. Since defects, including interfaces, reduce the symmetry of the systems, many perturbations will need to be performed for some of these models to accurately assess the phonon properties. Abinit will also be used to calculate the superconducting properties (electron-phonon coupling and transition temperature) of select structures. Accurate determination of the electron-phonon coupling is very computationally demanding, requiring dense k-point and q-point grids. Abinit parallelizes over k-points, bands, and perturbations; so it is particularly suitable for use on large machines with many cores. Current: undetermined amount Justification: Requested: 150000 A specific reason has been given: I need to complete a few more DFPT calculations with Abinit, which works very well on Blues. The extra time will be very helpful to this project. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System

1 0

[LCRC Accounts] Project Allocation Request
by accounts＠lcrc.anl.gov 16 Feb '15

16 Feb '15

Hello, A change in allocation has been requested: Requester: sunhwan (Sunhwan Jo) Project: entropy Title: Quantifying protein-protein binding with greatly scalable multiple copy algorithms of NAMD Description: In PMF-based framework, a set of geometric and conformational restraints is applied to the proteins to reduce sampling noise and accelerate the convergence of the resulting free energy profile. These biases are rigorously accounted for to produce the absolute binding free energy. To enhance the PMF convergence, we will combine the umbrella sampling with Hamiltonian and temperature (ℋ and T) replica-exchange molecular dynamics (REM) algorithm. In the US/(ℋ,T)-REMD simulation approach, multiple copies of the molecular  systems are simulated concurrently, but  all with different  conditions, e.g., umbrella potential (Hamiltonians) or temperature. Attempts are periodically made to exchange configurations between different systems using a Metropolis-type Monte Carlo acceptance criterion, insuring Boltzmann-weighted statistics. Such REMD  methodology is extremely scalable, yet also very effective to sample a rugged free energy surface. We anticipate the simulation systems will be comprised of ~50,000 atoms and using at least 255 replicas concurrently. Because of its large size, we plan to use primarily Mira for production and Fusion will be used for initial system preparation and development of enhanced methodology in PMF-based framework. All planned simulations will be carried out by the open-source NAMD molecular dynamics software. The software engine used for the planned simulations is NAMD 2.10 with Charm++ 6.4.0. We have tested t he performance on BG/Q Mira. The scaling of parallel performance was linear up to 512 cores for our test system comprised of 100,000 atoms without using restraint potential and achieved the speed of about 0.025 s/step. Using restraint potential reduces the parallel performance significantly (~0.2 s/step). The expected number of project member is 3. I, Sunhwan Jo, recently joined LCF as a postdoctoral appointee and will be the main person performing code improvement and algorithm development under the supervision of Wei Jiang (LCF) and Benoit Roux (UChicago). Current: undetermined amount Justification: Requested: 200000 A specific reason has been given: We are testing entropy estimation method with a newly developed solute tempering methodology. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System

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