On the Nature of Bonding in Synthetic Charged Molecular Alloy [P7ZnP7]4- Cluster and Its Relevant [P7]3- Zintl Ion.
Ontology highlight
ABSTRACT: Charged molecular alloys and Zintl ions are of interest in synthetic chemistry. However, their chemical bonding has seldom been elucidated using modern quantum chemistry tools. Herein, we report on in-depth chemical bonding analyses for a charged molecular alloy C 2 [P7ZnP7]4- cluster and its relevant Zintl ion C 3v [P7]3- ligand, making use of electronic structure calculations at PBE0/def2-TZVP level, natural bond orbital and orbital composition analyses, canonical molecular orbitals, and adaptive natural density partitioning (AdNDP). The computational data show that C 3v [P7]3- Zintl ion has three isolated, negatively charged, bridging P sites. Such charges are largely P 3p lone-pairs in nature, but they also participate in secondary P-P bonding along the bridging sites. C 2 [P7ZnP7]4- cluster is formulated as [P7]2-[Zn]0[P7]2-, in which [P7]2- ligands maintain the structural and bonding integrity of [P7]3- Zintl ion despite their difference in charge state. Two [P7]2- ligands collectively bind with Zn center via four bridging P sites, resulting in a quasi-tetrahedral ZnP4 core with the eight-electron counting. This bonding picture can alternatively be rationalized using the superatom concept. The Zn-P bonds are weak with a bond order of around 0.5, because the P centers have partial nonbonding 3p character, akin to 3p2 lone-pairs albeit with a lower occupation number.
SUBMITTER: You XR
PROVIDER: S-EPMC6645155 | biostudies-literature | 2018 Sep
REPOSITORIES: biostudies-literature
ACCESS DATA