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Workshop on HPC in India Chemical Dynamics in Aqueous Media Amalendu Chandra Department of Chemistry, Indian Institute of Technology Kanpur, India 208016 ATIP 1 st Workshop on HPC in India @ SC-09
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-092 Hydrogen bonded (tetrahedral) structure of water
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-093 Hydrogen bond fluctuations in water and aqueous solutions
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-094 Excess proton in water
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-095 Experimental Methods X-ray and Neutron Scattering Low frequency Raman ( < 200 cm -1 ) Time Resolved Infrared Spectroscopy Transient hole burning studies using IR laser
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-096 Pump-probe signal at different delay times Variation of H-bond distance with time Relaxation time ~ 1.0 ps G.M.Gale etal PRL, 82, 1068 (1999) = ~ 100-200 fs, ~ 1-2 ps A. Tokmakoff and coworkers JCP (2005) M.D. Fayer and coworkers, PNAS (2007)
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-097 Computation of Aqueous Systems
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-098 Ab initio Molecular Dynamics Forces are calculated from electronic structure calculation that are performed on-the-fly as the MD trajectory is generated. Car-Parrinello Method: R. Car and M. Parrinello, Phys. Rev. Lett., 55, 2471 (1985) J. Hutter et al. CPMD, MPI Stuttgart and IBM Zurich
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-099 A.Chandra and coworkers, JPC/A (2008); JCP (2008) OH stretch frequency vs time in liquid water
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0910 Frequency vs hydrogen bond distance (pure D 2 O )
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0911 Dynamics of vibrational spectral diffusion: Hole creation and subsequent dynamics from nonequilibrium probability distributions Hole creation: Monte Carlo algorithm
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0912 Dynamics after hole creation: Excitation in blue/red Experiments: G.M. Gale et al PRL (1999)
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0913 Time dependence of average frequency after hole creation 1 ~ 100 fs (dynamics of intact hydrogen bonds) 2 ~ 2 ps (lifetimes of hydrogen bonds) s ~ 100 cm -1 (intermolecular stretching/bending vibrations) A. Chandra and coworkers, JPC/A (2008); JCP (2009)
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0914 ScH 2 O Supercritical water 673K/0.0221 573K/0.0338 423K/0.0334 298K/0.0334 A.K Soper et al., JCP, 106, 249 (1996)
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0915 Correlations between OD frequency and D..O distance A. Chandra and coworkers, JPC/A (2008)
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0916 Proton Transfer in water Eigen Zundel complex
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0917 Mobility of H 3 O + in liquid water D H 3 O + = 9.31x10 -5 cm 2 /s D H 2 O = 2.30x10 -5 cm 2 /s Mobility of OH - in liquid water D OH _ = 5.3x10 -5 cm 2 /s M.E. Tuckerman, D.Marx and M. Parrinello, Nature, 417, 925 (2002) A.Chandra, M. Tuckerman and D.Marx, PRL (2007); Acc. Chem. Res. (2006) Proton Migration Dynamics
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0918 Protonic defects in water clusters Where is the protonic defect located? Is there any proton transfer in clusters? A. Bankura and A. Chandra, JCP (submitted)
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Describes chemically relevant part of large system using quantum mechanics (QM) and rest by molecular mechanics (MM) QM/MM Technique Long Range (LR) Short Range (SR) QM Density H 3 O + /OH - in different carbon nanotube systems Effects of confinement Quantum-classical simulations
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0920 Financial support: DST, CSIR, BRNS, MCIT (Government of India) AvH Foundation (Germany) Group members:
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A. ChandraATIP 1 st Workshop on HPC in India @ SC-0921 IIT Kanpur ….
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