Stoichiometric glass formers: vitrify upon cooling, not molecular glasses, not mixtures or alloys, isovalenl susbstitutions like AsSbS3 are excluded.

cooformulavitrifyqmg*crystallizeother*references
3:22V+3VIP2Se3, As2(S,Se,Te)3, Sb2S3 P2S3Sb2(Se,Te)3P2Te3 (ne)[Popescu00]
2III+3VIB2(O,S,Se)3, Al2O3   [Popescu00,Rao02]
4:2IV+2VI(Si,Ge)(O,S,Se)2 Sn(S,Se)2SnTe2 (ne)[Popescu00]
II+2VIIZnCl2, BeF2    
VI+2VITeO2**   [Popescu00]
2VISeSTe [Popescu00]
3V  As, SbP (uk) 
IV+VI  (Ge,Sn)(S,Se,Te) [Popescu00]
B   B (uk) 
4IV  C, Si, Ge  
II+IV+2V   CdGeP2, CdGeAs2, CdSiAs2[Sharma89]
I+III+2VI    [Sharma89]

* qmg – quasi-molecular glasses, sm – solid mixture/solution, ne – does not exist, uk – unknown.

** The building block is the trigonal bipyramid involving lone pair.

References