Li2GeMo3O8: a novel reduced molybdenum oxide containing Mo3O13 cluster units

Abstract

The crystal structure of the title compound, dilithium germanium trimolybdenum octaoxide, consists of distorted hexagonal-close-packed oxygen layers with stacking sequence ABAC along [001] that are held together by alternating lithium–germanium and molybdenum layers. The two Li+ and Ge4+ ions all have site symmetry 3m. and occupy, respectively, tetrahedral and octahedral sites in the ratio 2:1. The Mo atom has a formal oxidation state of +3.3 and occupies an octahedral site (site symmetry .m.) and forms strongly bonded triangular cluster units [Mo—Mo distance = 2.4728 (8) Å] involving three MoO6 octahedra that are each shared along two edges, constituting an Mo3O13 unit.

Keywords

• crystal structure
• reduced molybdenum oxide
• triangular Mo3 cluster
• lithium
• germanium