硼在化学中具有重要作用,生物学和材料科学。双原子过渡金属硼化物(MBs)是许多络合物和材料的组成部分,它们呈现出独特的电子结构,具有有趣和独特的性质,以及在这里分析的各种键合方案。在本文的第一部分,我们对第一行过渡金属硼化物的实验和理论研究进行了综述,即,ScB,TiB,VB,CrB,MnB,FeB,CoB,NiB,CuB,和ZnB;第二行过渡金属硼化物,即,YB,ZrB,NBB,MoB,TcB,RuB,RhB,PdB,AgB,和CdB;和第三行过渡金属硼化物,即,LaB,HfB,TAB,WB,ReB,OSB,IrB,PtB,AuB,和HgB。因此,在第二部分,使用B3LYP通过DFT计算研究第二行和第三行MB,TPSSh,和MN15函数和,在某些情况下,通过多参考方法,MRCISD+Q,结合aug-cc-pVQZ-PPM/aug-cc-pVQZB基础集。具体来说,粘结距离,离解能,频率,偶极矩,并报告了自然的NPA费用。沿着三行的MB分子之间的比较,并分析了它们的异同。还描述了双原子硼化物的键合;发现,除了RhB(X1Σ+),最近发现它形成了四重债券,RuB(X2Δ)和TcB(X3Σ-)也在其X态下形成四重σ2σ2π2π2键。此外,为了填补现有文献中存在的空白,在这里,我们计算TcB分子。
Boron presents an important role in chemistry, biology, and materials science. Diatomic transition-metal borides (MBs) are the building blocks of many complexes and materials, and they present unique electronic structures with interesting and peculiar properties and a variety of bonding schemes which are analyzed here. In the first part of this paper, we present a review on the available experimental and theoretical studies on the first-row-transition-metal borides, i.e., ScB, TiB, VB, CrB, MnB, FeB, CoB, NiB, CuB, and ZnB; the second-row-transition-metal borides, i.e., YB, ZrB, NbB, MoB, TcB, RuB, RhB, PdB, AgB, and CdB; and the third-row-transition-metal borides, i.e., LaB, HfB, TaB, WB, ReB, OsB,
IrB, PtB, AuB, and HgB. Consequently, in the second part, the second- and third-row MBs are studied via DFT calculations using the B3LYP, TPSSh, and MN15 functionals and, in some cases, via multi-reference methods, MRCISD+Q, in conjunction with the aug-cc-pVQZ-PPM/aug-cc-pVQZB basis sets. Specifically, bond distances, dissociation energies, frequencies, dipole moments, and natural NPA charges are reported. Comparisons between MB molecules along the three rows are presented, and their differences and similarities are analyzed. The bonding of the diatomic borides is also described; it is found that, apart from RhB(X1Σ+), which was just recently found to form quadruple bonds, RuB(X2Δ) and TcB(X3Σ-) also form quadruple σ2σ2π2π2 bonds in their X states. Moreover, to fill the gap existing in the current literature, here, we calculate the TcB molecule.