A novel crystalline SiCO compound.
Ab initio evolutionary structural searches have been performed on SixCyO2(x+y) compounds. A novel structure, with SiC2O6 stoichiometry and the P21/c space group is calculated to be stable against decomposition within a wide pressure window from 7.2 to 41 GPa, and metastable under ambient conditions. It consists of CO3 units, linked to SiO6 octahedra, supporting previous experimental studies. The evolution of the carbon environment towards tetrahedral CO4 units, thus resembling the crystal chemistry of silicon, is predicted at higher pressures.
MALTA-Consolider Team and Departamento de Física Teórica, Universidad de Valladolid, E-47011 Valladolid, Spain. miriam.marques@uva.es.
Miriam
M
Marqués
Angel
A
Morales-García
José Manuel
JM
Menéndez
Valentín G
VG
Baonza
José Manuel
JM
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