• Søndergaard-Pedersen, Simone
• Nielsen, Morten Bormann
• Bremholm, Martin

Abstract

High pressure synthesis is an important method in the search for new compounds that in many cases can be quenched to ambient conditions. Therefore high pressure syntheses push the boundaries of solid state chemistry.<br/>There is a large current interest in the metal dichalcogenides with their unique crystal structures and electrical properties.1,2 Up until now, the most sulfur rich phase in the Bi-S phase diagram was Bi2S3.3 For BiS2 the Bi atoms have anisotropic charge distribution and more complex structures are expected when comparing the layered structures of transition metal dichalcogenides.<br/>The possibilities of using high pressure synthesis to discover new phases in the Bi-S binary system were investigated as early as the 1960’s.4 The research led to discovery of a compound with BiS2 stoichiometry, but no structure solution of BiS2 was reported. A reason behind making this new phase is to study the physical properties since the related compound Bi2S3 is known to be a thermoelectric material.5 <br/>In this research the BiS2 compound was synthesized by a high pressure and high temperature method using a multi-anvil large volume press and the structure was solved by single crystal diffraction. The structure contains Bi atoms in distorted square-based pyramidal coordination to five surrounding sulfur atoms. The results will be displayed together with a comparison to other metal dichalcogenide compounds. <br/>Experimental details and physical properties will also be presented together with theoretical calculations of the electronic band structure using density functional theory about the compound at the presentation<br/>

Topics

• density
• impedance spectroscopy
• compound
• single crystal
• phase
• theory
• anisotropic
• layered
• density functional theory
• phase diagram
• band structure