Evidence of indirect spin-spin coupling in crystalline and glassy As-chalcogen compounds

Nuclear quadrupole resonance (NQR) studies on crystalline and glassy As-S/Se compounds reveal that the spin echo intensities as a function of pulse separation in the Hahn echo sequence exhibit oscillations superimposed on an exponential decay, given by the spin-spin relaxation time, T2. We have conducted systematic investigations of the nature of these T2 oscillations in glassy and crystalline As2S3 and As 2Se3. T2 oscillations in c-As2S 3 at 71.94 MHz are of the order of a kHz. T2 oscillations were also observed in glassy As2S3 and As 2Se3. We will present calculations of indirect spin coupling between inequivalent As atoms to explain the nature of the T 2 oscillations in glassy and crystalline As2S3 and As2Se3. © 2003 Elsevier B.V. All rights reserved.

Duke Scholars

Author Julio Cesar Facelli Biostatistics & Bioinformatics, Division of Translational Bi ...