Abstract
This paper presents a multi-coefficient correlation method based on quadratic configuration interaction with .single and double excitations (MC-QCISD) and basis sets using segmented contraction and having the same exponential parameters in the s and p spaces. The results are comparable to a previous multi-coefficient correlation method based on coupled cluster theory with less efficient correlation-consistent basis sets, and they are better than a previous multi-coefficient correlation method based on Møller-Plesset fourth order perturbation theory with single, double, and quadruple excitations with correlation-consistent basis functions. The mean unsigned error per bond of the MC-QCISD method is 0.72 kcal/mol. The new method should be very efficient for computing geometries of open-shell transition states.
Original language | English (US) |
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Pages (from-to) | 6111-6116 |
Number of pages | 6 |
Journal | Journal of Physical Chemistry A |
Volume | 104 |
Issue number | 26 |
DOIs | |
State | Published - 2000 |