COMPUTATION OF HIGH-ENERGY VIBRATIONAL EIGENSTATES - APPLICATION TO C6H5D

被引:34
作者
WYATT, RE
机构
[1] Department of Chemistry and Biochemistry, University of Texas at Austin, Austin
关键词
D O I
10.1063/1.470154
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
In this study, a two loop iteration scheme, similar to one developed recently [Phys. Rev. E 51, 3643 (1995)], is applied to the computation of high energy vibrational eigenstates in 21-mode planar C6H5D. The computational method is based upon the use of a spectral filter to extract a small number of eigenpairs (near the test input energy E) from the interior of the dense energy spectrum. In the outer iteration loop, a very effective filter, the Green function G(E)=(El-H)(-1), is used to drive the Lanczos recursion algorithm through a small number of steps (frequently <10). The result is a small tridiagonal representation of the Green function. The Lanczos algorithm converges quickly because the desired eigenvalues, those near the test energy, are mapped to the extreme edges of the spectrum of the filter. In order to apply the Green function to the current Lanczos vector, a matrix partitioning technique is combined with a perturbation-iteration method in the inner iteration loop. The Green function-lanczos algorithm, GFLA, was then used to compute eigenstates for 21-mode planar C6H5D near the energy of the upsilon=3 CD overtone (about 6700 cm(-1)). These computations were done using an active space with the dimension 20000. The resulting eigenfunctions were then subjected to several types of analysis, including basis state and vibrational mode distributions. It is shown that the energetic distribution of basis functions in the eigenvectors exhibits multifractal scaling (finer features built upon coarser features). (C) 1995 American Institute of Physics.
引用
收藏
页码:8433 / 8443
页数:11
相关论文
共 61 条
[21]   A GENERAL, ENERGY-SEPARABLE POLYNOMIAL REPRESENTATION OF THE TIME-INDEPENDENT FULL GREEN OPERATOR WITH APPLICATION TO TIME-INDEPENDENT WAVEPACKET FORMS OF SCHRODINGER AND LIPPMANN-SCHWINGER EQUATIONS [J].
HUANG, YH ;
KOURI, DJ ;
HOFFMAN, DK .
CHEMICAL PHYSICS LETTERS, 1994, 225 (1-3) :37-45
[22]   ANALYTIC CONTINUATION OF THE POLYNOMIAL REPRESENTATION OF THE FULL, INTERACTING TIME-INDEPENDENT GREEN-FUNCTION [J].
HUANG, YH ;
ZHU, W ;
KOURI, DJ ;
HOFFMAN, DK .
CHEMICAL PHYSICS LETTERS, 1993, 214 (05) :451-455
[23]  
IUNG C, 1993, J CHEM PHYS, V99, P226
[24]  
IUNG C, IN PRESS J CHEM PHYS
[25]  
Jennings A., 1992, MATRIX COMPUTATIONS
[26]   EXTRACTION OF EIGENSTATES FROM AN OPTICALLY PREPARED STATE BY A TIME-DEPENDENT QUANTUM-MECHANICAL METHOD - TOWARD SIMULATION OF INTERMEDIATE CASE RADIATIONLESS TRANSITIONS [J].
KONO, H .
CHEMICAL PHYSICS LETTERS, 1993, 214 (02) :137-143
[27]   TIME-DEPENDENT QUANTUM-MECHANICAL METHODS FOR MOLECULAR-DYNAMICS [J].
KOSLOFF, R .
JOURNAL OF PHYSICAL CHEMISTRY, 1988, 92 (08) :2087-2100
[28]   AN ITERATION METHOD FOR THE SOLUTION OF THE EIGENVALUE PROBLEM OF LINEAR DIFFERENTIAL AND INTEGRAL OPERATORS [J].
LANCZOS, C .
JOURNAL OF RESEARCH OF THE NATIONAL BUREAU OF STANDARDS, 1950, 45 (04) :255-282
[30]  
LOWDIN PO, 1968, INT J QUANTUM CHEM, V11, P867