The photodissociation of N,N-dimethylformamide: A complete active space self-consistent field study

The S-0, S-1, and T-1 equilibrium geometries of N,N-dimethylformamide (NNDMF) and transition state structures of the HC(O)-N(CH3)(2) and HC(O)N(CH3)-CH3 bond cleavages in the S-1 and T-1 states were determined with the complete active space self-consistent field method using the 6-31G{*}{*} basis set. The surface intersections among the S-0, S-1, and T-1 states were optimized with the state-averaged complete active space self-consistent field method. The most probable mechanisms, leading to different products for the NNDMF photodissociation at 193 nm, were provided in the present paper. The obtained mechanisms are slightly different from those proposed previously on the basis of qualitative analyses of state correlation and electronic configurations between the reactants and products. This is discussed in detail. (C) 2002 American Institute of Physics