CHEM01200604005 A. K. Pathak - Homi Bhabha National Institute

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neutral and anionic) and solvent molecules (water, ammonia and carbon dioxide) with different size have been presented and discussed in a systematic manner to understand the process of microsolvation. A general extrapolation model based on microscopic theory has also been developed for prediction of bulk detachment energy of excess electron from the finite size cluster data. The proposed thesis is to be submitted to the Homi Bhabha National Institute for the Doctor of Philosophy (PhD) degree. For convenience of presentation, different aspects of the present work have been discussed in eight different chapters of the thesis. Brief descriptions of the arrangements of different chapters in the thesis are given below. Chapter 1: This is the introductory chapter of the proposed thesis and describes in brief the microsolvation and motivation of this work. A brief overview about the minimum energy search procedure, electron correlation, basis set, ab initio and DFT methods are discussed. A method based on Monte Carlo and simulated annealing for finding global optimized structures is also discussed. Chapter 2: This chapter is dedicated to minimum energy structures and energy of hydrated clusters of various anionic and neutral chemical species in order to understand the process of microhydration. At present halogen dimer radical anions (Cl •− 2 , Br •− 2 & I •− 2 ), carbonate radical anion (CO •− 3 ), carbonate anion (CO 2− 3 ), nitrate anion (NO − 3 ) and halogen dimer (Cl 2 , Br 2 & I 2 ) are taken to study microhydration. The growth motif of all the hydrated clusters is also followed. xvi
Chapter 3: This chapter describes IR spectra of hydrated cluster of anionic solutes whose structures are discussed in chapter 1. Out of these systems, experimentally measured IR spectra are available for Cl •− 2 .nH 2 O cluster. The IR spectra of Cl •− 2 .nH 2 O cluster is presented in detail and compared with the reported experimental spectra. With the increase in number of solvent water molecules in hydrated clusters, the number of minimum energy configurations with close in energy for each size of hydrated clusters is expected to increase. Thus weighted average properties of clusters become more meaningful. Structures of hydrated clusters where solvent molecules are in the second shell i.e. not connected directly to the solute Cl • 2 ⎯, are also considered. Weighted average molecular properties are calculated based on the statistical population of different minimum energy configurations of a particular size of hydrated cluster at 100 K. Fourier transform to the dipole and velocity auto-correlation function is done to include dynamical contribution to the calculated IR spectra. Chapter 4: This chapter is dedicated to discuss on bulk property, e.g. the solubility of halogen gas in water. It is well known that bromine gas is more soluble in water, than chlorine gas but no theoretical understanding is available in literature. Structures and properties of halogen gas (Cl 2 , Br 2 & I 2 ) - water clusters are studied to understand the solubility order of halogen gases in water medium. It is observed that the halogen molecules remain as charge separated ion-pair in presence of solvent molecules. The extent of charge separation indeed explains the solubility order of the halogen gases in water. xvii
Page 1 and 2: MICROSOLVATION OF CHARGED AND NEUTR
Page 3 and 4: STATEMENT BY AUTHOR This dissertati
Page 5 and 6: Dedicated to my Daughter, Wife and
Page 7 and 8: CONTENTS Page No. SYNOPSIS LIST OF
Page 9 and 10: CHAPTER 4 Solubility of Halogen Gas
Page 11 and 12: 7.3.4. IR and Raman Spectra 117-121
Page 13 and 14: S Macroscopic Microscopic Dual leve
Page 15: molecular level interaction during
Page 19 and 20: In this system the conformers of a
Page 21 and 22: LIST OF FIGURES Page No. Fig. 1.1 2
Page 23 and 24: Fig. 2.6 54 (I) Plot of calculated
Page 25 and 26: (IIIA) Cl 2 .3H 2 O; (IIIB) Br 2 .3
Page 27 and 28: Fig. 6.3 104-105 Calculated scaled
Page 29 and 30: LIST OF TABLES Page No. Table. 2.1
Page 31 and 32: CHAPTER 1 Introduction 1.1. Microso
Page 33 and 34: 1.2. Motivation 1.2.1. Macrosolvati
Page 35 and 36: ulk water and pure neutral water cl
Page 37 and 38: insight about the electronic struct
Page 39 and 40: Newton -Raphson (NR) method expand
Page 41 and 42: potential energy surface for these
Page 43 and 44: terms, the energy can be written in
Page 45 and 46: Boyd proposed the use of Gaussian t
Page 47 and 48: eported experimental findings. Theo
Page 49 and 50: hydrated halide series, X¯.nH 2 O,
Page 51 and 52: anions (Cl •− 2 , Br •− 2 &
Page 53 and 54: geometrical parameters close to MP2
Page 55 and 56: symmetrical DHB, SHB or WHB arrange
Page 57 and 58: of I-I axis and having the least I-
Page 59 and 60: Br •− 2 .nH 2 O hydrated cluste
Page 61 and 62: VI-F VI-G VII-A VII-B VII-C VII-D V
Page 63 and 64: To see the effect of hydration on t
Page 65 and 66: Five minimum energy structures disp
Page 67 and 68:
arrangements. In total, it has one
Page 69 and 70:
NO 3 − .nH2 O (n ≥ 6), a few eq
Page 71 and 72:
V-E V-F V-G V-H V-I VI-A VI-B VI-C
Page 73 and 74:
VII-D VII-E VII-F VII-G VII-H VII-I
Page 75 and 76:
VIII-K VIII-L Fig.2.2. Fully optimi
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clusters. Hydrated cluster having c
Page 79 and 80:
However, these calculations do not
Page 81 and 82:
Table 2.1. Weighted average energy
Page 83 and 84:
Where, E[I •− 2 .nH 2 O] is the
Page 85 and 86:
The variation of the weighted avera
Page 87 and 88:
CHAPTER 3 IR Spectra of Water Embed
Page 89 and 90:
ecome more meaningful. At present,
Page 91 and 92:
I-A II-A II-B III-A III-B III-C III
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Cluster experiments are carried out
Page 95 and 96:
3350-3500 cm -1 (scaling factor ~0.
Page 97 and 98:
these systems, X. nH 2 O (X= Br 2
Page 99 and 100:
CHAPTER 4 Solubility of Halogen Gas
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including polarized and diffuse fun
Page 103 and 104:
and I 2 systems. The most stable st
Page 105 and 106:
Cl Cl Br Br I I VA VB VC Cl Cl Br B
Page 107 and 108:
(Br δ+ -Br δ- ) in the studied hy
Page 109 and 110:
stabilization energy does not follo
Page 111 and 112:
80 Cl 2 .nH 2 O (n=1-8) 80 Br 2 .nH
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separated ion pair in presence of s
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adical ( • OH) reacts with HCO 3
Page 117 and 118:
most stable conformer for each size
Page 119 and 120:
The structures of the hydrated clus
Page 121 and 122:
Table 5.1. Calculated absorption ma
Page 123 and 124:
molar extinction coefficient value
Page 125 and 126:
ammonia. 61-62 Hydrogen bonded wate
Page 127 and 128:
stable minimum energy structure is
Page 129 and 130:
IV-A IV-B V-A V-B V-C VI-A VI-B VI-
Page 131 and 132:
6.3.3. Vertical Ionization Potentia
Page 133 and 134:
311++G(2d,2p) level, the scaling fa
Page 135 and 136:
K(NH 3 ) 4 K(NH 3 ) 5 IR Intensity
Page 137 and 138:
CHAPTER 7 Structure, Energetics and
Page 139 and 140:
Thus Monte Carlo based simulated an
Page 141 and 142:
I I I I I I I I A B C D I I I I I I
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interaction as well as solvent-solv
Page 145 and 146:
Table 7.1. Various energy parameter
Page 147 and 148:
change in VDE is observed. This is
Page 149 and 150:
symmetric C-O stretching mode of CO
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to the maximum charge transfer of t
Page 153 and 154:
CHAPTER 8 A Generalized Microscopic
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possible breakdown of these laws ma
Page 157 and 158:
P 7 P , , P , ,, 1 ∂ 2
Page 159 and 160:
M DE = (r, ω)C DE , (r,
Page 161 and 162:
known. However, for most of the com
Page 163 and 164:
The calculated bulk detachment ener
Page 165 and 166:
espect to experimentally measured v
Page 167 and 168:
References 1. Ohtaki, H.; Radani, T
Page 169 and 170:
29. Turi, L.; Sheu, W.; Rossky,P.J.
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61. (a) Ehrler, O. T.; Neumark, D.
Page 173 and 174:
LIST OF PUBLICATIONS *1. “σ/σ
Page 175 and 176:
13. “Vibrational analysis of I
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CHEM01200604005 A. K. Pathak - Homi Bhabha National Institute

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