Using Lebedev grids, sine spherical harmonics, and monomer contracted basis functions to calculate bending energy levels of HF trimer

作     者：Wang, XG Carrington, T 

作者机构：Univ Montreal Dept Chim Montreal PQ H3C 3J7 Canada 

出 版 物：《JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY》 (理论与计算化学杂志)

年 卷 期：2003年第2卷第4期

页      面：599-608页

核心收录：

学科分类：07[理学] 0703[理学-化学] 

主　　题：HF trimer Lebedev grid contracted basis Lanczos algorithm 

摘      要：We calculate energy levels of a six-dimensional bending Hamiltonian for HF trimer using a finite basis representation (FBR) in conjunction with the Lanczos eigensolver. We improve on our previous method [J. Chem. Phys. 115, 9781 (2001) using three techniques: (1) Lebedev s quadrature scheme is used to reduce the size of quadrature grid by a factor of 3.4. (2) Since the barrier separating the two equivalent versions of HF trimer is high and wide, it is a good approximation to confine the bending motion to one well by using sine spherical harmonics basis functions (this reduces the size of the basis by a factor of 8). (3) The sine spherical harmonic basis is contracted for each monomer to generate a very efficient basis. It is shown that the best approach is to combine all the three techniques.