Magnetoresistance in pulsed fields, band structure calculations and charge-density wave instability in (TSeT) 2Cl

Diffuse X-rays measurements assign the 26 K metal-semimetal transition in (TSeT) 2Cl, where TSeT = tetraselenotetracene, to the stabilization of a 2k F=c∗/4 charge-density wave ground state. Tight-binding extended Hückel band calculations suggest that 2k F yields to a partial nesting of the four conduction bands. Transverse magnetoresistance experiments performed up to 37 T confirm the previous observation of SdH oscillations. The 0 + Landau level is evidenced for the first time.