Although methods to determine optimal Hashin–Shtrikman bounds for polycrystals of cubic to monoclinic symmetry have been described, the calculation of bounds for triclinic crystals has not previously been possible. The recent determination of elastic moduli of common minerals with low symmetry provides motivation to extend the Hashin–Shtrikman formulation to lower symmetry. Here, Hashin– Shtrik...

The structure of the title salt, C(24)H(20)P(+)·H(8)B(3) (-), at 120 (2) K has triclinic (P1) symmetry with an unusual Z = 5, although there is pseudosymmetry observed with the tetraphenylphosphonium cations exhibiting I symmetry. One of the anions is disordered over two sets of sites with refined occupancies of 0.478 (11) and 0.522 (11).

Type II dehydroquinase is a small (150-amino-acid) protein which in solution packs together to form a dodecamer with 23 cubic symmetry. In crystals of this protein the symmetry of the biological unit can be coincident with the crystallographic symmetry, giving rise to cubic crystal forms with a single monomer in the asymmetric unit. In crystals where this is not the case, multiple copies of the...

The structure of 2-[(4-chlorophenylazo) cyanomethyl] benzoxazole, C15H9ClN4O (I), has triclinic ([Formula: see text]) symmetry. The structure displays N-H ⋯ N hydrogen bonding. The structure of 2-[(arylidene) cyanomethyl] benzoxazoles, C17H10N2O3 (II), has triclinic ([Formula: see text]) symmetry. The structure displays C-H ⋯ N, C-H ⋯ C hydrogen bonding. In (I), the chlorophenyl and benzoxazole...

A study of the magnetic and structural properties of the double perovskite Ba2GdMoO6 has been performed. The crystal structure distorts from the ideal cubic (Fm3m) structure to the tetragonal space group I4/m at 220 K, before undergoing a second distortion to a triclinic system (I1) at 80 K. The phase transition to triclinic symmetry is also evident in magnetic susceptibility measurements. The ...

Octakis(m-tolyloxymethyl)naphthalene, the first Type I spider host produced, crystallises from tetraglyme forming a novel channel structure with the host molecule attaining exact D(2) symmetry. The (flexible) channel structure is retained for guest CS(2), the host now only having exact C(2) symmetry. The octa-sulfone octakis(m-tolylsulfonylmethyl)naphthalene is also of Type I in its triclinic D...

The triclinic unit cell of the title compound, N(2)H(6) (2+)·2C(6)H(3)N(2)O(4) (-)·2H(2)O, contains one doubly protonated hydrazine cation which lies on an inversion centre, two symmetry-related singly deprotonated 6-carboxy-pyridazine-3-carboxyl-ate anions and two symmetry-related solvent water mol-ecules. The anions inter-act via hydrogen bonds to form double ribbons which are bridged by hydr...

The type of the mesophase is altered by a small change in the molecular architecture, i.e. increasing the number of alkyl chains attached to the mesogenic core at terminal positions. Lamellar (1D) and columnar (2D) phases are formed for molecules with one and three terminal chains, respectively. For those with two chains 3D phases are observed with either cubic or triclinic symmetry structure.