The calculation of photoionisation cross sections of simple polyatomic molecules by L2 methods
The calculation of photoionisation cross sections of simple polyatomic molecules by L2 methods
复制标题
L2法计算简单多原子分子的光电离截面
DOI：
10.1016/0370-1573(91)90041-j
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
R. Moccia
中科院分区：
文献类型：
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作者：
I. Cacelli;Vincenzo Carravetta;A. Rizzo;R. Moccia
本文讨论了分子由于单光子或双光子吸收引起的光致电离截面的计算，重点讨论了如何利用分子中丰富的电子束缚态计算方法来获得有关电子连续体的有用和详细的信息。因此，本报告的主要注意力集中在允许从L2基组计算中提取与电子连续体有关的性质的方法。第一部分概述了计算微分电离截面所需的电子连续体的特征，以及一种可进行系统改进的方法，该方法基于反应性K矩阵，从L2能量变分或L2基组RPA计算中获得所有需要的跃迁矩阵元素。然后，在概述了与Born-Oppenheimer近似的含义和规范的选择有关的问题之后，简要回顾了Stieltjes矩理论，该理论允许从离散化的表示中计算连续统中的振子强度密度。剩下的部分报告了一些计算单光子和双光子过程的具体例子。
This article is concerned with the calculation of the photoionisation cross section of molecules due either to the one-photon or, in view of the increasing interest in the nonlinear optical processes, to the two-photon absorption.The emphasis is put upon the approaches which may exploit the extensive wealth of know-how for the calculation of the electronic bound states of molecules to gain useful and detailed information about the electronic continuum. Thus the main attention of this report is devoted to the methods which permit the extraction of properties pertaining to the electronic continuum fromL2basis-set calculations. The first part outlines the features characterizing the electronic continua required to calculate the differential ionisation cross section, and a method, amenable to systematic improvements, based upon the reactionK-matrix to obtain all the required transition matrix elements either from anL2energy-variational or from anL2basis-set RPA calculation. Then, following an overview of the problems connected with the implications of the Born-Oppenheimer approximation and with the choice of the gauge, a brief review is presented of the Stieltjes moment theory which permits the evaluation of the oscillator-strength density in the continuum from a discretized representation. The remaining part reports some specific examples of calculations for the one-photon and the two-photon processes.
DOI：
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发表时间：
2022
期刊：
影响因子：
--
作者：
Kusano Shuhei;Ichikura Yuma;Fujimoto Kazuhiro J.;Konishi Sae;Yamada Yuji;Hayashida Osamu;Toshiaki Matsubara and Keisuke Shirasaka;Satoshi Yabushita
通讯作者：
Satoshi Yabushita