NQR study of chalcogenide glasses Ge-As-Se

A three‐component Ge‐As‐Se system is studied by the nuclear quadrupole resonance (NQR) method on ⁷⁵As nuclei and by the nutation NQR spectroscopy. The NQR ⁷⁵As spectra of the glasses Ge_0.021As_0.375Se_0.604, Ge_0.043As_0.348Se_0.609 and Ge_0.068As_0.318Se_0.614reveal broad lines with two peaks assigned to the main structural unit of As₂Se₃. With increasing average coordination number (r?), the spectrum signals are shifted towards higher frequencies. At r? > 2.54, the spectrum becomes complex, which is a consequence of formation of more complex molecular structures in the glasses of high content of germanium. At fixed frequencies the asymmetry parameter η of the samples studied is determined. Copyright © 2011 John Wiley & Sons, Ltd.