Author:
Han Yingna,Xing Wandong,Yu Rong,Meng Fanyan
Abstract
The structural stability of hexagonal tungsten mononitride (WN) has been studied combining scanning transmission electron microscopy and first-principles calculations. The results show that the WC-type WN with vacancies of 6∼8 at% is more stable than the previously proposed MnP-type and NiAs-type structures. Due to the larger vibrational entropy of the WC-type WN, the vacancy concentration required to stabilize the WC-type structure is lower at high temperatures. The results demonstrate the importance of vacancies and configurational and vibrational entropies in the structural stability of compounds synthesized at high temperatures.
Funder
National Natural Science Foundation of China
Fundamental Research Funds for the Central Universities
Publisher
International Union of Crystallography (IUCr)
Subject
Materials Chemistry,Metals and Alloys,Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials