We studied the energetic behavior of the chlorinated cumuleneone series, including formyl chloride, chloroketene, propadienone chloride, and butatrienone chloride. Equation of motion- coupled cluster (EOM-CCSD) theory was employed to compute the electronically excited properties of these systems up to the vacuum ultraviolet (VUV) range (7 - 11 eV). We observe an increase of Rydberg character mixing with valence, which causes these highly energetic states to be more diffuse and therefore, more challenging to calculate. Thus, we explore the effects of diffuse basis functions, from aug-cc-pV(T+d)Z to t-aug-cc-pV(T+d)Z, to accurately predict the photophysical properties of the systems. A drop in the energy as more diffuse functions are added confirms the Rydberg character of these states. The predicted geometries and ionization potentials are in excellent agreement with the experimental photoelectron spectra for formyl chloride and chloroketene. Furthermore, there are similarities in the excitation character between the odd-numbered chains and the even-numbered chains. We predict a kinkiness in the structure of propadienone chloride while the linearity is preserved for butatrienone chloride. This indicates that the chlorine substitution does not significantly alter the structures of the cumuleneone series. The nonlinearity in the carbon chain causes propadienone chloride to disobey the energetic pattern of the entire series.

Study of highly excited states of chlorine substituted cumuleneone series with coupled cluster method

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.