Substantial Cd-Cd Bonding in Ca6PtCd11: A Condensed Intermetallic Phase Built of Pentagonal Cd, and Rectangular Cd4/2Pt Pyramids

TitleSubstantial Cd-Cd Bonding in Ca6PtCd11: A Condensed Intermetallic Phase Built of Pentagonal Cd, and Rectangular Cd4/2Pt Pyramids
Publication TypeJournal Article
Year of Publication2013
AuthorsGulo F, Samal SL, Corbett JD
Journal TitleInorganic Chemistry
Volume52
Pages10112-10118
Date Published09
Type of ArticleArticle
ISBN Number0020-1669
Accession NumberWOS:000326129000048
Keywordsau, ba, ca, chemistry, crystal-structure, gold substitution, networks, sr, systems, tunnels
Abstract

The novel intennetallic Ca(6)PtCc(11) is orthorhombic, Pnma, Z = 4,.with a = 18.799(2) A, b = 5.986(1) angstrom, c = 15.585(3) angstrom. The heavily condensed network contains three types of Parallel cadmium chains: apically strongly interbon'ded Cd-7 pentagonal bipyramids, linear Cd arrays, and rectangular Cd4/2Pt pyramids. All of the atoms have 11-13 neighbors. Calculations by means of the linear muffin-tin orbitals method in the atomic spheres approximation indicate that some Cd Cd interactions correspond to notably high Hamilton populations (1.07 eV per average bond) whereas the Ca-Ca covalent interactions (integrated crystal orbital Hamiltonian population) are particularly small (0.17 eV/bond). (Pt-Cd single bond metallic diameters,, and unusually uniform (A = 0.14 A). The Cd atoms.make major contributions to the stability of the phase via substantial Ss and Sp bonding, which include back donation of Cd Ss, Sp and Pt 5d into Ca 3d states in the principal bonding modes for Ca Cd and Ca Pt. Bonding Ca Ca, Ca Cd, and Cd Cd states remain above EF, and some relative oxidation of Ca in this structure seems probable. Ca6PtCd11 joins a.small group of other phases in which Cd clustering and Cd Cd bonding are important.

URL<Go to ISI>://WOS:000326129000048
DOI10.1021/ic401455c