List of Articles energy gaps Open Access Article Abstract Page Full-Text 1 - Steric effects on the Singlet–Triplet Energy Gaps of Seven Membered Ring silylenes, R2C6H6Si M. Nikoorazm E. Vessally E. Abolfathi Open Access Article Abstract Page Full-Text 2 - Electronic effects at 2 and 7 α–position of divalent unsaturated seven membered ring R2C6H6M (M=C, Si, Ge, Sn, Pb) Eynallah Abolfathi