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
[1]   FRACTAL DIMENSIONALITY OF WAVE-FUNCTIONS AT THE MOBILITY EDGE - QUANTUM FRACTAL IN THE LANDAU-LEVELS [J].
AOKI, H .
PHYSICAL REVIEW B, 1986, 33 (10) :7310-7313
[2]  
Beck Christian., 1993, CAMBRIDGE NONLINEAR, DOI [10.1017/CBO9780511524585, DOI 10.1017/CBO9780511524585]
[3]   EFFICIENT CALCULATION OF HIGHLY EXCITED VIBRATIONAL-ENERGY LEVELS OF FLOPPY MOLECULES - THE BAND ORIGINS OF H-3(+) UP TO 35000 CM(-1) [J].
BRAMLEY, MJ ;
TROMP, JW ;
CARRINGTON, T ;
COREY, GC .
JOURNAL OF CHEMICAL PHYSICS, 1994, 100 (09) :6175-6194
[4]   CALCULATION OF TRIATOMIC VIBRATIONAL EIGENSTATES - PRODUCT OR CONTRACTED BASIS-SETS, LANCZOS OR CONVENTIONAL EIGENSOLVERS - WHAT IS THE MOST EFFICIENT COMBINATION [J].
BRAMLEY, MJ ;
CARRINGTON, T .
JOURNAL OF CHEMICAL PHYSICS, 1994, 101 (10) :8494-8507
[5]   A GENERAL DISCRETE VARIABLE METHOD TO CALCULATE VIBRATIONAL-ENERGY LEVELS OF 3-ATOM AND 4-ATOM MOLECULES [J].
BRAMLEY, MJ ;
CARRINGTON, T .
JOURNAL OF CHEMICAL PHYSICS, 1993, 99 (11) :8519-8541
[6]  
BRUSSBACH H, 1993, CHEM PHYS, V177, P733
[7]   PROPERTIES OF VIBRATIONALLY EXCITED POLYATOMIC-MOLECULES AND THEIR ENERGY VARIATION - TRANSITION-MOMENT AND ENERGY SPACING DISTRIBUTIONS [J].
BUCH, V ;
RATNER, MA ;
GERBER, RB .
MOLECULAR PHYSICS, 1982, 46 (05) :1129-1140
[8]   A STATISTICAL WAVEFUNCTION MODEL FOR C-H/C-D OVERTONE LINEWIDTHS - APPLICATION TO C6H6, C6D6, C6HD5, C6HF5 [J].
BUCH, V ;
GERBER, RB ;
RATNER, MA .
JOURNAL OF CHEMICAL PHYSICS, 1984, 81 (08) :3393-3399
[9]   DISTRIBUTIONS OF ENERGY SPACINGS AND WAVEFUNCTION PROPERTIES IN VIBRATIONALLY EXCITED-STATES OF POLYATOMIC-MOLECULES .1. NUMERICAL EXPERIMENTS ON COUPLED MORSE OSCILLATORS [J].
BUCH, V ;
GERBER, RB .
JOURNAL OF CHEMICAL PHYSICS, 1982, 76 (11) :5397-5404
[10]  
Chatelin F., 1993, EIGENVALUES MATRICES