Abstract
A new model of defect structure for ordered niobium carbide is proposed. The model is a superimposure of two partially disordered M6X5 superstructures. The first of these is an energetically advantageous low-temperature ordered phase (spatial group C2), while the other is an auxiliary superstructure (space group C2/m) that serves to increase the contribution from configurational entropy to the free energy as the temperature rises. The superimposure of superstructures is due to an incomplete order–order phase transition and explains the reasons for the discrepancy between the experimental and calculated intensities of superstructure reflexes in the neutron diffraction patterns of the ordered phase.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Bulletin of the Russian Academy of Sciences: Physics
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
