摘要
用量子化学密度泛函理论(DFT),分别在B3PW91/Lan12DZ和B3PW91/6-31G的计算水平上,优化Ni离子水、羟基配合物几种可能的构型。分析比较了Ni(OH)_6^(4-)和Ni(H_2O)_6^(2+)化合物的几何参数、能量、前线轨道、电荷分布及振动频率。结果:优化的健参数中,Ni-O键长与文献的实验数据较一致。Ni(H_2O)_6^(2+)比Ni(OH)_6^(4-)更稳定,但后者更易吸引带正电荷的阳离子。从前线轨道图也可以看出,Ni(OH)_6^(4-)最高占据轨道HOMO主要集中于配体O上,易于向受体流动提供电子与带正电荷的阳离子结合。振动分析的Ni(H_2O)_6^(2+)和Ni(OH)_6^(4-)的红外吸收峰与实验值相一致。
The possible geometric structures of Ni（ Ⅱ ） aqua and hydroxyl complexes were optimized by means of density functional theory （DFT） at the B3PW91/Lanl2 DZ and B3PW91/6-31 G^＊＊ levels, respectively. The geometric parameters, energies, frontier molecular orbitals, atomic charges, and vibrational frequencies of complexes were analyzed and compared. The calculated results show that the Ni-O bond lengths are in good agreement with those of experiment. The structure of Ni（ H2O）6^2＋ is more stable than that of Ni （OH）6^4- but the last one is better at attracting cations. The shapes of frontier molecular orbital also show that the highest occupied molecular orbitals （HOMO） of Ni（ OH）6^4- are mainly located on the O atoms of the ligands,which is benefit for charge transferring between the ligands and the acceptors and bonding with the cation group. The IR spectrums of the Ni complexes consist with the experiment data as well.
出处
《计算机与应用化学》
CAS
CSCD
北大核心
2007年第8期1014-1018,共5页
Computers and Applied Chemistry
基金
国家自然科学基金(20573009).
关键词
镍离子配合物
电子结构
红外谱
密度泛函理论
Ni（ Ⅱ ） complexes, electronic Structures, IR spectrum, density functional theory
