Synthesis-enabled exploration of chiral and polar multivalent quaternary sulfides† † Electronic supplementary information (ESI) available: Experimental details including synthesis descriptions as well as methods, figures, and tables pertinent to characterization techniques used: powder and single crystal X-ray diffraction, 17-BM in situ powder XRD, scanning electron microscopy, energy dispersive X-ray spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, DFT calculations, solid-state diffuse reflectance spectroscopy, magnetic measurements. Crystallographic data: CSD 2089782–2089797. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/d1sc03685h

ABSTRACT: An innovative method of synthesis is reported for the large and diverse (RE)6(TM)x(Tt)2S14 (RE = rare-earth, TM = transition metals, Tt = Si, Ge, and Sn) family of compounds (∼1000 members, ∼325 contain Si), crystallizing in the noncentrosymmetric, chiral, and polar P63 space group. Traditional synthesis of such phases involves the annealing of elements or binary sulfides at elevated temperatures. The atomic mixing of refractory components technique, presented here, allows the synthesis of known members and vastly expands the family to nearly the entire transition metal block, including 3d, 4d, and 5d TMs with oxidation states ranging from 1+ to 4+. Arc-melting of the RE, TM, and tetrel elements of choice forms an atomically-mixed precursor, which readily reacts with sulfur providing bulk powders and large single crystals of the target quaternary sulfides. Detailed in situ and ex situ experiments show the mechanism of formation, which involves multiphase binary sulfide intermediates. Crystal structures and metal oxidation states were corroborated by a combination of single crystal X-ray diffraction, elemental analysis, EPR, NMR, and SQUID magnetometry. The potential of La6(TM)x(Tt)2S14 compounds for non-linear optical applications was also demonstrated. Synthesis from atomically-mixed precursors opens up a phase space to hundreds of chiral and polar sulfide semiconductors with almost any transition metal in variable oxidation states.

SUBMITTER: Akopov G 

PROVIDER: S-EPMC8597832 | biostudies-literature |

REPOSITORIES: biostudies-literature