Record Details

Selective bond breaking mediated by state specific vibrational excitation in model HOD molecule through optimized femtosecond IR pulse: A simulated annealing based approach

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Selective bond breaking mediated by state specific vibrational excitation in model HOD molecule through optimized femtosecond IR pulse: A simulated annealing based approach
 
Creator SHANDILYA, BK
SEN, S
SAHOO, T
TALUKDER, S
CHAUDHURY, P
ADHIKARI, S
 
Subject INFRARED-LASER PULSES
1ST ABSORPTION-BAND
DEPENDENT SCHRODINGER-EQUATION
PHOTODISSOCIATION DYNAMICS
GLOBAL OPTIMIZATION
QUANTUM CONTROL
ANALYTICAL SHAPES
WATER
H2O
FRAGMENTATION
 
Description The selective control of O-H/O-D bond dissociation in reduced dimensionality model of HOD molecule has been explored through IR+UV femtosecond pulses. The IR pulse has been optimized using simulated annealing stochastic approach to maximize population of a desired low quanta vibrational state. Since those vibrational wavefunctions of the ground electronic states are preferentially localized either along the O-H or O-D mode, the femtosecond UV pulse is used only to transfer vibrationally excited molecule to the repulsive upper surface to cleave specific bond, O-H or O-D. While transferring from the ground electronic state to the repulsive one, the optimization of the UV pulse is not necessarily required except specific case. The results so obtained are analyzed with respect to time integrated flux along with contours of time evolution of probability density on excited potential energy surface. After preferential excitation from vertical bar 0, 0 > (vertical bar m, n > stands for the state having m and n quanta of excitations in O-H and O-D mode, respectively) vibrational level of the ground electronic state to its specific low quanta vibrational state (vertical bar 1, 0 > or vertical bar 0, 1 > or vertical bar 2, 0 > or vertical bar 0, 2 >) by using optimized IR pulse, the dissociation of O-D or O-H bond through the excited potential energy surface by UV laser pulse appears quite high namely, 88% (O-H; vertical bar 1, 0 >) or 58% (O-D; vertical bar 0, 1 >) or 85% (O-H; vertical bar 2, 0 >) or 59% (O-D; vertical bar 0, 2 >). Such selectivity of the bond breaking by UV pulse (if required, optimized) together with optimized IR one is encouraging compared to the normal pulses. (C) 2013 AIP Publishing LLC.
 
Publisher AMER INST PHYSICS
 
Date 2014-10-15T08:34:22Z
2014-10-15T08:34:22Z
2013
 
Type Article
 
Identifier JOURNAL OF CHEMICAL PHYSICS, 139(3)
http://dx.doi.org/10.1063/1.4813127
http://dspace.library.iitb.ac.in/jspui/handle/100/14695
 
Language en