MO-Theoretical Description of Electronic Structures of Tricentric Bisdesmiphiles in the Ground and Excited States
MO-Theoretical Description of Electronic Structures of Tricentric Bisdesmiphiles in the Ground and Excited States
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三中心双半亲基态和激发态电子结构的 MO 理论描述
DOI：
10.1246/bcsj.69.3395
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发表时间：
1996
影响因子：
4
通讯作者：
K. Yamaguchi
中科院分区：
文献类型：
--
作者：
Y. Yoshioka;D. Yamaki;G. Maruta;T. Tsunesada;K. Takada;T. Noro;K. Yamaguchi
针对惠斯根、费尔斯通等人对三中心双亲水分子基态电子结构的相互矛盾的争论，给出了一个系统的分子轨道理论描述。近似自旋投射但大小一致的UHF和UMP方法弥补了单重态UHF和UMP波函数中存在的自旋污染效应带来的伪影，合理地给出了不同自旋的不同轨道(DODS)分子轨道描述，适用于含氧偶极子(如O3和CH2OO)以及没有八重态稳定的1，3-双自由基(如OCH2O和CH2CH2CH2)。RHF方法对双自由基性质较少的二氮和氮化甜菜碱提供了被广泛接受的分子轨道描述，而RMP方法即使对弱双自由基性质的物种也能很好地适用。它们被成功地用于计算三心物种的非自由基环和双自由基开式之间的相对能量，三心双原子的单重态和三重态能隙。
A systematic MO-theoretical description of electronic structures of tricentric bisdesmiphiles in the ground state is presented in response to contradictory arguments on the biradical character of the species by Huisgen, Firestone, and others. The approximately spin-projected but size-consistent (AP) UHF and UMP methods remedy artifact arising from the spin contamination effect involved in the singlet UHF and UMP wavefunctions, giving reasonable a different-orbitals-for-different-spins (DODS) MO description for oxygenated dipoles such as O3 and CH2OO and 1,3-biradicals without octet stabilization such as OCH2O and CH2CH2CH2. The RHF method provides well-accepted MO description for diszonimum and nitrilium betaines having little biradical character, and the RMP method works well even for species with weak biradical character. They are successfully applied to calculating relative energies between nonradical ring- and biradical open-forms of tricentric species, singlet–triplet energy gaps of tricentric biradi...