Mo$_{2}$BC: Chemical and External Pressure Effects
POSTER
Abstract
The intermetallic Mo$_{2}$BC is a superconductor with a T$_{C}$ = 6.6 K and a crystalline face centered orthorhombic structure. Chemical pressure generated by changing the carbon concentration decreases T$_{C}$ in a non monotonic rate. Complete elimination of carbon, changes the crystalline structure from orthorhombic to body centered tetragonal, and reducing T$_{C}$ to about 5.8 K. At ambient pressure the compound presents a minimum in the resistivity at 50 K, which could be related to a Kondo anomaly. In polycrystalline samples we applied external pressures up to 4.8 GPa with a diamond anvil cell, which induced negative changes in the superconducting transition at a rate dT$_{C}$/dP = - 0.03 K/GPa. These results will be discussed in terms of the electronic band structure.
*Acknowledgements: (R. F.) Thanks SEP-Promep 20050643 UJATAB-CA175.