α-Lactose monohydrate: a redetermination at 150 K

The structure of the monohydrate of α-4-(β-D-galactopyran­osido)-D-glucopyran­ose, more commonly known as α-lactose monohydrate, C₁₂H₂₂O₁₁·H₂O, has been previously studied by single-crystal diffraction at ca 296 K [Beevers & Hansen (1971). Acta Cryst. B27, 1323–1325; Fries et al. (1971). Acta Cryst. B27, 994–1005; Noordik et al. (1984). Z. Kristallogr. 168, 59–65]. This redetermination at low temperature [150 (2) K] shows improved precision of geometry. Graph-set analysis of the hydrogen-bonding motifs is presented for the first time.