Structural Phase Transition in Li2C2

✍ Scribed by Uwe Ruschewitz; Rainer Pöttgen

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: German
• Weight: 159 KB
• Volume: 625
• Category: Article
• ISSN: 0372-7874
• DOI: 10.1002/(sici)1521-3749(199910)625:10<1599::aid-zaac1599>3.0.co;2-j

✦ Synopsis

Pure polycrystalline Li 2 C 2 could be obtained by the reaction of lithium and graphite flakes in an arc-melting furnace. X-ray powder investigations on these samples confirm the crystal structure given by Juza, Wehle, and Schuster (Immm, No. 71, Z = 2) which is isotypic to Rb 2 O 2 and Cs 2 O 2 . At about 500 °C a reversible phase transition (1 st order) to a cubic modification (Fm 3 m, No. 225, Z = 4) has been observed. This high temperature modification can be described as an antifluorite-structure with disordered C 2 2± dumbbells.