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arXiv · 1505.01407

Multireference X-Ray Emission and Absorption Spectroscopy calculations from Monte Carlo Configuration Interaction

J. P. Coe·M. J. Paterson
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Abstract

We adapt the method of Monte Carlo configuration interaction to calculate core-hole states and use this for the computation of X-ray emission and absorption values. We consider CO, CH$_{4}$, NH$_{3}$, H$_{2}$O, HF, HCN, CH$_{3}$OH, CH$_{3}$F, HCl and NO using a 6-311G** basis. We also look at carbon monoxide with a stretched geometry and discuss the dependence of its results on the cutoff used. The Monte Carlo configuration interaction results are compared with EOM-CCSD values for X-ray emission and with experiment for X-ray absorption. Oscillator strengths are also computed and we quantify the multireference nature of the wavefunctions to suggest when approaches based on a single reference would be expected to be successful.

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J. P. Coe, M. J. Paterson. 2015-05-06. Multireference X-Ray Emission and Absorption Spectroscopy calculations from Monte Carlo Configuration Interaction. https://doi.org/10.1007/s00214-015-1656-0

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