C. Trindle, S. N. Datta, B. Mallik
Dec 31, 1997
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0
Influential Citations
61
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Journal
Journal of the American Chemical Society
Abstract
We judge the energetic sequence of spin states in substituted methylenes by ab initio multiconfigurational computations and, where feasible, density functional modeling techniques. The best of these calculations reproduce well-established singlet−triplet gaps in X−C−Y species, in which X can be phenyl and Y can be H, methyl, or chloro. Similar computations on p-phenylene-coupled Y−methylenes and meta-coupled Y−methylenes support the suggestion by Zuev and Sheridan that bis(chloromethylene)-p-phenylene has a singlet diradical ground state. However, despite the density functional computations' support for those authors' suggestion that bis(chloromethylene)-m-phenylene has a singlet ground state, we find that our best MCSCF calculations place the quintet ground state suggested by the simplest theory almost equal in energy to that singlet.