Exploring the Physical Properties of Tungsten Diselenide (WSe2): A First Principle Approach

The physical properties of crystalline compounds are highly essential for predicting their applications in various nanodevices. Density functional theory is very useful in that regard. Herein, some physical properties such as structural stability, and electronic, optical and mechanical properties of two-phase bulk WSe2 have been comparatively investigated by first principle calculations. Band structure calculations elucidate that the materials are indirect band gap semiconductors having band gap energy in the range 1-1.5 eV. It was observed that the hexagonal crystal has higher absorption coefficients compared to the trigonal phase. Analysis of elastic constants of the materials carried out using the Born criteria method indicates that all systems are mechanically stable at room temperature. Our findings are in close agreement with the previous experimental and theoretical results, this further suggests that the materials are promising in optoelectronics applications.