Stable silicon‐centered localized singlet 1,3‐diradicals XSi(GeY2)2SiX: theoretical predictions

Abstract

AbstractSome localized singlet 1,3‐σ‐diradicals, XSi(GeY2)2SiX, (X = H, CH3, SiH3, C(CH3)3, NH2 for X = F; Y = H, CH3, OH, NH2, SiH3 for X = H) are theoretically designed by the orbital phase theory, the density functional theory (DFT) calculations , the second order Møller–Plesset perturbation theory (MP2), and the complete active space self‐consistent field (CASSCF) methods. The silicon‐centered singlet diradicals are more stable than the lowest triplets and than the bicylic σ‐bonded isomers if the isomers exist. The most stable singlet diradicals are not the π‐type diradicals, but the σ‐type diradicals where the radicals interact with each other through the SiGe bonds in the four‐membered rings. Copyright © 2007 John Wiley & Sons, Ltd.