Role of anion size, magnetic moment, and disorder on the properties of the organic conductor κ-(BETS)2Ga1-xFexCl4-yBry

Shubnikov–de Haas and angular dependent magnetoresistance oscillations have been used to explore the role of anion size, magnetic moment, and disorder in the organic conductors κ‐(BETS)2GaBr4κ‐(BETS)2GaBr4 and κ‐(BETS)2FeCl2Br2κ‐(BETS)2FeCl2Br2 in the isomorphic class κ‐(BETS)2Ga1‐xFexCl4‐yBryκ‐(BETS)2Ga1‐xFexCl4‐yBry. The results, combined with previous work, show correlations between the anion composition (Ga1‐xFexCl4‐yBry)(Ga1‐xFexCl4‐yBry) and the superconducting transition temperature, effective mass, Fermi surface topology, and the mean free path.