Structures and Electron Affinities of Some Alkylthio Radicals and Their Anions

Seven different density functional theory methods have been employed to predict the molecular structures and adiabatic electronic affinities of RS/RS^-(R=CH₃, C₂H₅, n-C₃H₇, n-C₄H₉, n-C₅H₁₁, i-C₃H₇, t-C₄H₉) radicals and their anions. The basis used is of double-ζ plus polarization quality with additional s-and p-type diffuse functions, labeled as DZP+ +. The most reliable adiabatic electron affinities, obtained by B3LYP methods,are 1.838eV (CH₃S), 1.925eV(C₂H₅S), 1.939eV(n-C₃H₇S), 1.961eV(n-C₄H₉S), 1.969eV(n-C₅H₁₁S), 2.023eV(i-C₃H₇S), and 2.055eV(t-C₄H₉S), respectively. Compared with the experimental values, the average absolute error of the B3LYP method remained only 0.047eV.