{"title":"Structure stabilization effect of vacancies and entropy in hexagonal WN.","authors":"Yingna Han, Wandong Xing, Rong Yu, Fanyan Meng","doi":"10.1107/S2052520622006096","DOIUrl":null,"url":null,"abstract":"<p><p>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.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":null,"pages":null},"PeriodicalIF":1.3000,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Acta crystallographica Section B, Structural science, crystal engineering and materials","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1107/S2052520622006096","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2022/7/16 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
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.
期刊介绍:
Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials publishes scientific articles related to the structural science of compounds and materials in the widest sense. Knowledge of the arrangements of atoms, including their temporal variations and dependencies on temperature and pressure, is often the key to understanding physical and chemical phenomena and is crucial for the design of new materials and supramolecular devices. Acta Crystallographica B is the forum for the publication of such contributions. Scientific developments based on experimental studies as well as those based on theoretical approaches, including crystal-structure prediction, structure-property relations and the use of databases of crystal structures, are published.