Umbrella inversions of cyclononatetraenylidenes at ab initio and DFT
Keywords: کاربن; Carbene; Singlet; Triplet; Racemization; C9H8; C9H7Br; C9H7Cl; C9H7F; 2-, 3-, 4-, or 5-Halo-2,4,6,8-cyclononatetraenylidenes; Ab initio; DFT;