4-[(Z)-2-(methylsulfanyl)ethenyl]-1-phenyl-1H-1,2,3-triazole: an order-disorder (OD) interpretation of twinning.

The title compound, C(11)H(11)SN(3), crystallizes as twins with a twin volume fraction of 0.4232 (13). An order-disorder (OD) interpretation gives a plausible explanation of the crystallization behaviour. The structure is a polytype with a maximum degree of order (MDO). The contact plane is interpreted as being composed of a fragment of the second MDO polytype. The planes of the triazole and phenyl rings are twisted by 36.88 (6)°. Molecules are connected via C-H···N hydrogen bonds, forming layers parallel to (100). The layers can be arranged in geometrically different but energetically virtually equivalent ways, giving rise to polytypism.