Tokunosuke Watanabe

The Crystal Structures of Magnesium Formate Dihydrate and Manganous Formate Dihydrate

Magnesium and manganous formate dihydrates crystallize in the space group P 2 1 / c , with the unit cell dimensions:

Crystal Structure of Cupric Benzoate Trihydrate Cu(C6H5COO)23H2O

Cupric benzoate trihydrate crystallizes in the monoclinic system, space group I 2/ c , with four formula units in a unit cell of dimensions, a =6.98, b =34.12, c =6.30 A; \(\beta{\doteqdot}90\)°. There are two kinds of benzoate groups. The carboxyl oxygen atoms of benzoate group I are in direct contacts with copper atoms, while those of group II are coordinated to copper atoms through water molecules. Each copper atom is situated at the center of a deformed octahedron consisted of four water molecules and two oxygen atoms from benzoate group I. The octahedra are linked, by sharing two water molecules, into a column parallel to the c -axis. Within this column, copper atoms lie on a line at an interval of 3.15 A, which suggests the presence of magnetic anisotropy.

A Twinning Structure in Crystals of Aniline Hydrobromide, C6 H5 NH3 Br

A new twinning structure of aniline hydrobromide was found by means of an x-ray study. The twin elements are two-fold screw axes parallel to [011] and [0\bar11] through the origin. This type of twinning can be seen, in some cases, by an microscopic observation, especially by etch patterns on a cleaved plane parallel to (100). The formation of the twin will probably due to the difference of the growth rates in different crystallographic directions.