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Journal of Chemical Sciences [Formerly: Proceedings (Chemical Sciences)] Vol. 124, No. 1, January 2012 CONTENTS Special issue on Structure, Reactivity and Dynamics Foreword .........................................................................11–12 3 Dynamics of atom tunnelling in a symmetric double well coupled to 2 an asymmetric double well: The case of malonaldehyde 1 – > S Ghosh and S P Bhattacharyya . 13 19 x <P 0 FQuantum Phase Space Trajectory_ for the tunnelling and Cis-Cis isomerization of Malonaldehyde. -1 -2 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 <x> Shape change as entropic phase transition: A study using Jarzynski 0.2 relation Moupriya Das, Debasish Mondal and Deb Shankar Ray . 21–28 Y 0.0 Shape of a system plays an important role in non-equilibrium transitions between two thermalized states when the system size is finite. It is shown that -0.2 modulation of the shape of an enclosure may make the resident Brownian particles feel an entropic phase transition. -1.2 -0.6 0.0 0.6 1.2 X Fitness landscapes in natural rocks system evolution: A conceptual DFT treatment Fe2O3 χ 6 oxides (eV) 8 Soma Duley, Jean-Louis Vigneresse 5 Al2O3 SiO 2 TiO2 – 4 MgO and Pratim Kumar Chattaraj . 29 34 FeO 7 (eV) 7 ω minerals MnO CuS2O 3 3 Cu(SH) 6 6 2 Density functional theory provides the chemical reactivity descriptors, CaO CuSO3 Cu(OH) SH- 2 5 5 Cu2S2O3 2 SO3 (eV) CuS ω Cu2SO 3 CuO (electronegativity, hardness and electrophilicity) of major oxides as observed in Na2O S SO 4 4 2 2 Cu(SH) K O Cu2S 1 2 Cu(OH) natural igneous rocks. They are plotted within a fitness landscape diagram, with 3 3 Cu2SO2 Cu2O CuSO 2 0 2 the principles of minimum electrophilicity (MEP) and maximum hardness 0 1 2 3 4 5 6 2 3 4 5 6 7 η (eV) η (eV) (MHP) as guides towards the region of higher stability. Natural rocks evolve (a) (b) within the three poles of silica (SiO2), alkalis (K2O and Na2O) and redox agent (Fe3O2). An application to S-bearing copper compounds is also presented. Hydrogen bonded networks in formamide [HCONH2]n (n =1− 10) clusters: A computational exploration of preferred aggregation patterns A Subha Mahadevi, Y Indra Neela and G Narahari Sastry .....35–42 Manifestation of hydrogen bond cooperativity as a function of increasing cluster size and varying arrangement of molecules is explored using formamide [HCONH2]n (n = 1 – 10) clusters based on DFT calculations. 1 2 Contents Useofanintensemicrowavelasertodissociateadiatomic molecule: Theoretical prediction of dissociation dynamics Amita Wadehra and B M Deb . 43–50 Taking the CO molecule as a Morse oscillator, the quantum dynamics of its dissociation under an intense microwave laser is followed theoretically and computationally. The time-dependent probability density is examined along with high-order harmonics generation and above-threshold dissociation. TDDVR (a) A quantum-classical simulation of a multi-surface multi-mode + nuclear dynamics on C6H6 incorporating degeneracy among electronic states MCTDH (b) Subhankar Sardar and Satrajit Adhikari. 51–58 Intensity Experiment (c) The photoelectron spectra of benzene is quantum - classically simulated using parallelized time dependent discrete variable representation (TDDVR) method, where the degeneracy among different states is considered in the realistic model Hamiltonian of corresponding system. 11.4 11.6 11.8 12.0 12.2 Energy (eV) 2 2 + B E2g A2u band of C6 H6 Understanding proton affinity of tyrosine sidechain in hydrophobic confinement T G Abi, T Karmakar and S Taraphder . 59–63 A density functional study is presented on the effect of hydrophobic confinement on the proton affinity of a tyrosine sidechain suspended within a single-walled carbon nanotube. The bulky sidechain encounters unfavorable steric interactions with the surrounding wall that primarily determines the observed lower reactivity of the sidechain. 1e-11 Full dimensional quantum scattering study of the H2 + CN reaction H2 (v1) + CN (v2) HCN + H 1e-12 S Bhattacharya, A Kirwai, Aditya N Panda 1e-13 /s] – 3 and H-D Meyer . 65 73 [cm k 1e-14 Present (v1v2)=(10) Present (v1v2)=(01) Rate constants for the H2 + CN reaction are presented for the reagents in their Ref. 29 (v1v2)=(00) 1e-15 Expt Ref. 6 (v1v2)=(01) excited vibrational states by carrying out exact wave packet studies using Expt Ref. 2 (v1v2)=(01) Ref. 28 (v1v2)=(10) multiconfiguration time dependent Hartree method. Ref. 28(v1v2)=(01) 1e-16 1 2 3 4 5 1000/T[1/K] Dynamics of atomic clusters in intense optical fields of ultrashort duration Deepak Mathur and Firoz A Rajgara . 75–81 Intense, 10 fs long laser pulses have been used to irradiate gas-phase Ar15,000 clusters. When multiply ionized, these clusters Coulomb explode, producing fast Ar-ions. The strong-field, few-cycle dynamics produce different angle- dependent ion energy and ion yield functions from those in the longer pulse (>30 fs) regime. Contents 3 Bhageerath—Targeting the near impossible: Pushing the frontiers of atomic models for protein tertiary structure prediction B Jayaram, Priyanka Dhingra, Bharat Lakhani and Shashank Shekhar . 83–91 Sequence to structure prediction is made using Bhageerath and Bhageerath-H method. 5 10 Quenching vibrations by collisions in cold traps: A quantum study vi=1 v =2 + 1 + 4 1 4 i 10 for MgH (X @ )with He( S) vi=3 vi=4 v =5 ) i 2 3 10 D Caruso, M Tacconi, F A Gianturco and E Yurtsever . 93–97 2 10 + Cross Section (Å The quenching process of the MgH vibrational energy induced by collisions 1 with He has been characterized by extensive ab initio quantum calculations. 10 + + MgH (v=v )+He -> MgH (v=0) + He 0 i 10 -3 -2 -1 0 10 10 10 10 Collision Energy (K˚) Design of optimal laser pulses to control molecular rovibrational excitation in a heteronuclear diatomic molecule Sitansh Sharma, Gabriel G Balint-Kurti and Harjinder Singh . 99–104 State selective control of vibrational and rotational molecular dynamics in HF by optimally designed laser pulses with high yields is reported. Partition function of the two-dimensional nearest neighbour Ising models for finite lattices in a non-zero magnetic field M Vinothkumar, G Nandhini and M V Sangaranarayanan . 105–113 The variation of the specific heat with nearest neighbour interaction energies for various magnetic fields pertaining to a square lattice of 64 sites is evaluated. Dynamics study of a three-fold pseudo-Jahn–Teller system using the extended Longuet–Higgins formalism Biplab Sarkar and A J C Varandas . 115–120 Extended–Longuet–Higgins formalism provides a simple way to include the geometrical phase in the generalized Born–Oppenheimer equations of a three-fold Jahn–Teller system. 4 Contents Optimal control of the initiation of a pericyclic reaction in the electronic ground state Timm Bredtmann and Jörn Manz . 121–129 How to initiate a pericyclic reaction in the electronic ground state? An attempt is made to solve the problem by means of Optimal Control Theory by designing an optimal laser pulse with down-chirped pump-dump sub-pulses in the ultraviolet frequency and sub-10 femtosecond time domains. The theoretical approach is supported by experimental results. Structure and intermolecular vibrations of 7-azaindole-water 2:1 complex in a supersonic jet expansion: Laser-induced fluorescence spectroscopy and quantum chemistry calculation Montu K Hazra, Moitrayee Mukherjee, V Ramanathan and Tapas Chakraborty . 131–139 We have measured the low-frequency intermolecular vibrations of a 2:1 complex between 7-azaindole and water using laser-induced fluorescence spectroscopy in a supersonic jet expansion. The structure of the complex has been suggested by analysing these vibrations with the aid of the predictions of quantum chemistry calculation. e-F2 Scattering e-HCl Scattering 0.07 Vibrational excitation resulting from electron capture in LUMO of 14 NWE F2 and HCl – A treatment using the time-dependent wave packet 0.06 LCP-TDWP 12 LCP-TDWP approach 0.05 10 ) ) 2 0.04 2 (Å (Å 8 Bhavesh K Shandilya, Manabendra Sarma, Satrajit Adhikari 1←0 0.03 1←0 σ σ Exp 6 and Manoj K Mishra . 141–148 0.02 4 Houfek et al. Bardsey et al. 0.01 2 The vibrational excitation cross-sections in e-F2 and e-HCl scattering have been BO-NWE 0 0 calculated with local complex potential based time dependent wave packet 0 0.02 0.04 0.06 0.08 0.1 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Energy (Hartree) Energy (eV) approach and compared with those of other theoretical/experimental results. Tailoring approach for obtaining molecular orbitals of large systems Anuja P Rahalkar and Shridhar R Gadre . 149–158 Molecular tailoring approach, a fragment-based method, is employed for obtaining the complete set of MOs, for large molecular systems, without performing the calculation on the whole system. The benchmarks are performed on the diverse molecules including :-conjugated systems at HF and DFT levels of theory. Variation of diffusivity with the cation radii in molten salts of -18.3 (b) T = 1000K; Ag+ σ = 0.33 Å ( E = 16.214 kJ/mol ) superionic conductors containing iodine anion: A molecular cation A -18.4 σ = 0.53 Å ( E = 14.022 kJ/mol ) 0.8 cation A dynamics study Ag+ -18.5 /s ) 2 0.75 m -8 Srinivasa R Varanasi and S Yashonath . 159–166 ln D -18.6 0.7 D ( x 10 -18.7 Diffusivity exhibits a maximum when cation radius is varied in a molten salt 0.65 -18.8 containing iodide anion. Computed properties include radial distribution 0.6 function, diffusivity of cation and anion, velocity autocorrelation function, 0.32 0.4 0.48 0.56 0.64 0.9 0.95 1 1.05 1.1 σ -1 activation energy and intermediate scattering function.

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