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As2S crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. As1+ is bonded in a linear geometry to two equivalent S2- atoms. Both As–S bond lengths are 2.56 Å. S2- is bonded in a 4-coordinate geometry to four equivalent As1+ atoms.
Re4As6S3 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are two inequivalent Re4+ sites. In the first Re4+ site, Re4+ is bonded in a 6-coordinate geometry to three equivalent As+1.67- and three equivalent S2- atoms. All Re–As bond lengths are 2.66 Å. All Re–S bond lengths are 2.35 Å. In the second Re4+ site, Re4+ is bonded in a 6-coordinate geometry to four As+1.67- and two equivalent S2- atoms. There are a spread of Re–As bond distances ranging from 2.49–2.66 Å. Both Re–S bond lengths are 2.33 Å. There are four inequivalent As+1.67- sites. In the first As+1.67- site, As+1.67- is bonded in a tetrahedral geometry to four As+1.67- atoms. There are one shorter (2.48 Å) and three longer (2.50 Å) As–As bond lengths. In the second As+1.67- site, As+1.67- is bonded to three equivalent Re4+ and one As+1.67- atom to form a mixture of distorted corner and edge-sharing AsRe3As tetrahedra. In the third As+1.67- site, As+1.67- is bonded to three Re4+ and one As+1.67- atom to form a mixture of distorted corner and edge-sharing AsRe3As tetrahedra. In the fourth As+1.67- site, As+1.67- is bonded in a 3-coordinate geometry to three equivalent Re4+ atoms. S2- is bonded in a 3-coordinate geometry to three Re4+ atoms.