Comparative peculiarities of polytypy of crystals Cu(D-Ala)(L-Ser) and Cu2(D-Ala)(L-Ala)(D-Ser)(L-Ser)

Abstract

Atomic structures of two polytypic modifycations of crystals of mixed cooper (II) com- pound Cu(D-Ala)(L-Ser) with optically active α-alanine (Ala) and serine (Ser) were studied by the electron diffraction analysis method: modification I - a=9.26(2) Å, b=9.60(1) Å, c=4.98(1) Å, γ=91.2(3)°, Z=2, space group of symmetry P21; modification II - a=18.52(2) Å, b=9.60(1) Å, c=4.98(1) Å, γ=91.2(3)°, Z=4, space group of symmetry C21. It was demonstrated that the modifications of the crystals of two compounds Cu(D- Ala)(L-Ser) and Cu2(D-Ala)(L-Ala)(D-Ser)(L-Ser) with racemic amino acids, correspond- ingly, belong to the same family of polytypic modifications.