First-principle calculations of high-pressure phase transformations in RuC
School of Physics and Electronic Engineering, Jiangsu Normal University - Xuzhou 221116, PRC
Received: 2 January 2014
Accepted: 6 February 2014
The structural stabilities of RuC under high pressure have been studied by using first-principle calculations. Results show that RuC transforms from the ZB-type (zinc-blende-type) structure to a tetrahedral structure with space group I4mm at . The I4mm structure constructed by RuC5 pyramids is stable up to , above which the WC-type structure becomes energetically more favorable. An increase of the coordination number from 4 to 5 and then to 6 is observed accompanied by the phase sequence of ZB type WC type. Band structure calculations reveal that the ZB-type phase is a semiconductor while the I4mm and WC-type phases are metallic. Moreover, the mechanical properties of RuC in all three phases are discussed.
PACS: 62.20.de – Elastic moduli / 61.50.Ah – Theory of crystal structure, crystal symmetry; calculations and modeling / 71.15.Nc – Total energy and cohesive energy calculations
© EPLA, 2014