Potential energy surfaces, calculation configuration interaction

The C3H2 potential energy surface continued to find attention, computationally and experimentally. It was Herges and Mebel,67 who reported in 1994, that the experimental and calculated IR spectra of T-36 agree quite well if a more sophisticated treatment including configuration interaction (QCISD/6-31G ) is... 

K. Stark, H-J. Werner, An accurate multireference configuration interaction calculation of the potential energy surface for the F+H2 HF+H reaction, J. Chem. Phys. 104 (1996) 6515. 

M.P. Deskevich, M.Y. Hayes, K. Takahashi, R.T. Skodje, D.J. Nesbitt, Multireference configuration interaction calculations for the F(2P)+HC1 HF+C1(2P) reaction A correlation scaled ground state (12A ) potential energy surface, J. Chem. Phys. 124 (2006) 224303. 

The author should also like to thank Professor Walter S. Koski, who suggested the 0+ + N2 problem to her and who collaborated in its theoretical treatment, and Dr. Aaron Pipano, who collaborated in the configuration-interaction computation of the 0+ + N2 reaction. The configuration-interaction calculations on the 0+ + N2 potential-energy surface were supported in part by BRL under Contract No. DAAD05-70-0027 and in part by the Atomic Energy Commission. 

An extended basis set may even be required for describing the potential energy surface of the neutral (la,4). This is especially true for highly fluxional molecules where very different geometries have similar energies (see the discussion below). The calculations should be extended beyond the SCF level using methods which account for electron correlation, e.g. configuration interaction or MCSCF techniques (20). 

This reaction proceeds adiabatically via the two lowest potential energy surfaces, and with a degeneracy factor of 1/3 each. These surfaces are usually obtained by analytically fitting the energies obtained from an ab initio computational quantum chemistry calculation at various nuclear positions. In Ref. 67, the contracted configuration interaction (CCI) ab initio data of Walch and Jaffe was used for both potential energy surfaces. The details of the analytical representation of the and surfaces can be found in Refs. 67 and 70, respectively. 

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