Superconducting high-pressure phases of disilane.
High-pressure structures of disilane (Si(2)H(6)) are investigated extensively by means of first-principles density functional theory and a random structure-searching method. Three metallic structures with P-1, Pm-3m, and C2/c symmetries are found, which are more stable than those of XY(3)-type candidates under high pressure. Enthalpy calculations suggest a remarkably wide decomposition (Si and H(2)) pressure range below 135 GPa, above which three metallic structures are stable. Perturbative linear-response calculations for Pm-3m disilane at 275 GPa show a large electron-phonon coupling parameter lambda of 1.397 and the resulting superconducting critical temperature beyond the order of 10(2) K.
Jin
Xilian
X
State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China.
Meng
Xing
X
He
Zhi
Z
Ma
Yanming
Y
Liu
Bingbing
B
Cui
Tian
T
Zou
Guangtian
G
Mao
Ho-Kwang
HK