NUCLEAR-QUADRUPOLE DOUBLE-RESONANCE IN AHSO4 (A EQUIVALENT-TO K, RB, CS, TL, NH4)

Nuclear quadrupole resonance (NQR) spectra of O-17, K-39, Rb-85, Rb-87 and Cs-133 have been measured in the low-temperature phases of KHSO4, RbHSO4, NH4HSO4 and TIHSO4 with the nuclear quadrupole double-resonance technique based on magnetic field cycling. The NQR results are related to the crystal structures of the low-temperature phases of these compounds.