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Electronic Characteristics of Quasi-2D Metallochloronitrides: Na(x)HfNCL (T_c=25 K)

R. Weht·A. Filippetti·W. E. Pickett
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Abstract

Local density functional results are presented for the electron-doped metallochloronitrides A(x)ZrNCl and A(x)HfNCl, A = Li or Na, which superconduct up to 25K. The alkali non-stoichiometry is treated in a virtual crystal approximation. The electronic structure is strongly two dimensional, especially in the conduction band region occupied by the carriers, because the states are formed from the in-plane orbitals d_xy, d_{x^2-y^2} of the metal ion and the p_x, p_y orbitals of the N ion. We predict a change of behavior at a doping level of x=0.3.

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R. Weht, A. Filippetti, W. E. Pickett. 1999-03-12. Electronic Characteristics of Quasi-2D Metallochloronitrides: Na(x)HfNCL (T_c=25 K). https://doi.org/10.1063/1.59601

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