Add time:07/29/2019         Source:sciencedirect.com

The heat capacity Cv(T) and unit cell volume V(T) temperature dependencies of lutetium borides LuB2 and LuB4 in the region of 2–300 К were analysed in the Debye-Einstein approximation. The characteristic temperatures of the Debye and Einstein components of boride heat capacity and thermal expansion were found. The anomalous contribution to the borides’ thermal characteristics was revealed. This contribution was attributed to the influence of two-level systems (TLS), formed in the subsystem of lutetium ions due to asymmetry in the way they are surrounded by the boron atoms in the boride crystal structure. The TLS influence is revealed on heat capacity temperature dependencies by the Schottky-type maxima at Tmax LuB2 =13.8 K, Tmax LuB4 =22.7 K, as well as by the negative contribution to the borides’ thermal expansion. The borides’ Grüneisen parameters corresponding to the heat capacity and thermal expansion TLS anomalies are negative, and amount to several 10 s of units.

We also recommend Trading Suppliers and Manufacturers of IRON BORIDE/ 99 (cas 12006-85-8). Pls Click Website Link as below: cas 12006-85-8 suppliers