High-Spin Stability of Triiminiummethane Ion
-A Comparative Study with Trimethylenemethane-

Masashi HATANAKA* and Ryuichi SHIBA

Department of Materials Science and Engineering, Graduate School of Engineering, Tokyo Denki University
2-2 Kanda-Nishiki-cho, Chiyoda-ku, Tokyo, 101-8457, Japan
*e-mail: mhatanaka@xug.biglobe.ne.jp

(Received: January 12, 2006; Accepted for publication: March 24, 2006; Published on Web: July 18, 2006)

High-spin stability of non-Kekule-type molecule triiminiummethane ion (TIM3+) is discussed using the semiempirical molecular orbital method. The triplet ground state 3A2' with a D3h geometry is predicted to lie below the Jahn-Teller distorted singlet states similar to trimethylenemethane (TMM). The lowest singlet states 1B1, 1B2 and 1A1 with C2v geometries are nearly degenerate. The spin-density distribution of the 3A2' state is calculated and the origin of the spin alignment is discussed relating to the spin-polarization rule characteristic of high-spin organic molecules. The valence bond analysis on the spin states of TIM3+ is also carried out.

Keywords: Non-Kekule-type molecules, Molecular orbital method, High-spin organic molecules, Spin density, Triiminiummethane ion

Abstract in Japanese

Text in English

PDF file(159kB)