Theoretical study of the photophysics of SF5CF3

The photophysical properties of trifluoromethyl sulfur pentafluoride (SF5CF3) are investigated with the HF, MP2, CIS, CC2, and TDDFT electronic structure theory methods. The potential-energy surface of the nearly degenerate pair of the lowest excited singlet states is found to be repulsive for stretching of the C-S and S-F bonds. The implications of these theoretical findings for the photophysical reactivity and photostability of the title compound in the atmosphere are discussed.