2021/09/07 by Nazmun Sadat Khan, Khan, Nazmun Sadat, B. Rahman Rano +7
Engineering · Materials Science · Physics and Astronomy · #Boron and Carbon Nanomaterials Research #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Metal and Thin Film Mechanics #Superconductivity (cond-mat.supr-con) #Superconductivity in MgB2 and Alloys
paper · pdf · doi:10.48550/arxiv.2109.02864
openalex publication_date 2021/09/07 · openalex created_date 2022/10/08 · openalex updated_date 2026/07/28
Very recently carbon-rich NaC6 with sodalite-like structure has been predicted to show superconducting transition temperature above 100 K at relatively low applied (compared to high-Tc hydrides) hydrostatic pressures. We have investigated the pressure dependent structural, elastic, electronic, superconducting state, and optoelectronic properties of NaC6 in this study. Some important thermophysical properties have also been explored. The elastic properties along with Poisson's and Pugh's ratios and optoelectronic parameters are investigated for the first time. NaC6 was found to be structurally stable only at high pressures at and above 40 GPa, in agreement with previous study. The compound is highly ductile and the chemical bonding is predominantly metallic in nature. The Debye temperature shows strong pressure dependence. The Gruneisen parameter also exhibits significant pressure dependence. The electronic band structure reveals metallic character and consists of highly dispersive and almost flat bands crossing the Fermi level. Both the electronic density of states at the Fermi level and repulsive Coulomb pseudopotential increase gradually with increasing pressure in the range 40 GPa to 70 Gpa. The degree of dispersion in the E(k) curves depend weakly on pressure both in the valence and conduction bands. The optical parameters spectra, studied for the first time, correspond well with the electronic band structure. NaC6 absorbs and reflects electromagnetic radiation quite efficiently in the mid-ultraviolet region. Superconducting transition temperatures of NaC6 have been estimated at different pressures and compared with previously reported values. The effects of various parameters on Tc have been discussed in details.