Glass formation and structure in non-oxide chalcogenide systems. The short range order of silver sulfide (Ag2S)-phosphorus sulfide (P2S5) glasses studied by phosphorus-31 MAS-NMR and dipolar NMR techniques

Glass formation and the local structure of ionically conductive crystalline and glassy compositions in the (Ag 2 S)(P x S 5 ) 1-x system have been investigated by 31 P magic-angle spinning (MAS) and spin-echo NMR. Glass formation encompasses the compositional range 0.5≤x≤0.67. 31 P MAS and spin-echo NMR data reveal striking differences in the local structures of the glasses and their crystalline counterparts. This result reinforces previous findings in related pseudobinary chalcogenide systems