Stark spectroscopy of an excited-state proton-transfer molecule: comparison of experimental and computational results for o-hydroxyacetophenone

Stark effect (electroabsorption) spectroscopy was used to determine the changes in dipole moment and polarizability that result from excitation of o-hydroxyacetophenone (OHAP) to its first excited state. A polyethylene matrix is used to minimize the possibility of hydrogen-bonding impurities that are known to alter the properties of molecules that undergo excited-state proton transfer (ESIPT). The results are compared to ab initio and AM1 calculations.