In the title compound, C(17)H(20)BrClNO(4)P, inter-molecular C-H⋯O and N-H⋯O hydrogen bonds form centrosymmetric R(2) (2)(10) dimers linked through O-H⋯O inter-molecular hydrogen bonds, which form centrosymmetric R(2) (2)(16) dimers. All these hydrogen bonds form chains along [010]. In addition, the crystal structure is stabilized by weak C-H⋯Br hydrogen bonds. The very weak intramolecular N-H⋯...

The title compound, C(8)H(8)INO(4)S, is a halogenated sulfon-amide, a medicinally important class of organic compounds. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds involving the carboxylic acid groups form characteristic centrosymmetric dimers. These dimers are further linked through centrosymmetric dimeric N-H⋯O inter-actions involving the amido H atom and a sulfonyl O atom....

We report that the hybrid organic-inorganic compound [(CH3)2NH2][Mg(HCOO)3] shows a marked dielectric transition around Tt∼ 270 K, associated to a structural phase transition from SG R3[combining macron]c (centrosymmetric) to Cc (non-centrosymmetric). This is the highest Tt reported so far for a perovskite-like formate that is thus a promising candidate to display electric order very close to r...

A previous analysis of the average intensity and mean-square intensity difference of Friedel opposites, confined to the space group P1 [Flack & Shmueli (2007). Acta Cryst. A63, 257-265], is here extended to all the non-centrosymmetric space groups. The present analysis presumes purely non-centrosymmetric content of the unit cell. An important result of this study is that the average intensity a...

A centrosymmetric stress cannot induce a polar response in centric materials; piezoelectricity is, for example, possible only in non-centrosymmetric structures. An exception is metamaterials with shape asymmetry, which may be polarized by stress even when the material is centric. In this case the mechanism is flexoelectricity, which relates polarization to a strain gradient. The flexoelectric r...

Centrosymmetric involutions in the symmetric group S2n are permutations π such that π = π−1 and π(i) + π(2n + 1 − i) = 2n + 1 for all i, and they are in bijection with involutions of the hyperoctahedral group. We describe the distribution of some natural descent statistics on 321-avoiding centrosymmetric involutions, including the number of descents in the first half of the involution, and the ...