Exploring the (H2C鈺怭H2)+:N-Base Potential Surfaces: Complexes Stabilized by Pnicogen, Hydrogen, and Tetrel Bonds
详细信息 查看全文
- 作者：Janet E. Del Bene ; Ibon Alkorta ; Jos茅 Elguero
- 刊名：Journal of Physical Chemistry A
- 出版年：2015
- 出版时间：December 3, 2015
- 年：2015
- 卷：119
- 期：48
- 页码：11701-11710
- 全文大小：475K
- ISSN：1520-5215
文摘
Ab initio MP2/aug鈥?cc-pVTZ calculations have been carried out to determine the structures, binding energies, and bonding properties of complexes involving the cation (H2C鈺怭H2)+ and a set of sp-hybridized nitrogen bases including NCCH3, NP, NCCl, NCH, NCF, NCCN, and N2. On each (H2C鈺怭H2)+:N-base surface, four types of unique equilibrium structures exist: a complex with a P路路路N pnicogen bond formed through the 蟺 system of (H2C鈺怭H2)+ (ZB-蟺); a complex with a P路路路N pnicogen bond formed through the 蟽 system of (H2C鈺怭H2)+ (ZB-蟽); a hydrogen-bonded complex with a P鈥擧路路路N hydrogen bond (HB); and a tetrel-bonded complex with a C路路路N bond (TB). Binding energies of complexes stabilized by the same type of intermolecular interaction decrease in the order NCCH3 > NP > NCCl > NCH > NCF > NCCN > N2. For a given base, binding energies decrease in the order ZB-蟺 > HB > ZB-蟽 > TB, except for a reversal of HB and ZB-蟽 with the weakest base N2. Binding energies of ZB-蟺, HB, and ZB-蟽 complexes increase exponentially as the corresponding P鈥擭 distance decreases, but the correlation is not as good between the binding energies of TB complexes and the intermolecular C鈥擭 distance. Charge-transfer energies stabilize all complexes and also exhibit an exponential dependence on the corresponding intermolecular distances. EOM-CCSD spin鈥搒pin coupling constants 1pJ(P鈥擭) for ZB-蟺 and ZB-蟽 complexes, and 2hJ(P鈥擭) for HB complexes increase quadratically as the corresponding P鈥擭 distance decreases. Values of 1tJ(C鈥擭) for TB are small and show little dependence on the C鈥擭 distance. 1J(P鈥擧) values for the hydrogen-bonded P鈥擧 bond in HB complexes correlate with the corresponding P鈥擧 distance, whereas values of 1J(P鈥擧) for the non-hydrogen-bonded P鈥擧 correlate with the P鈥擭 distance.