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Zinc-rich/copper-poor CuZnSnS (x = 0.2, CZTS) has been successfully produced in film and powder form using two non-aqueous solutions (of metal salts and thiourea) without the need for sulfurization during the annealing phase. A reaction route is proposed and the choices of the solvents (water, ethyleneglycol, ethanol, methanol) and of the tin source (tin chloride pentahydrate or anhydrous) discussed and justified. A pure and coarse-grained material is obtained with a mix of metal salts in methanol and thiourea in ethylene glycol. The tin pentahydrate salt seems a better alternative to the commonly used anhydrous chloride. [ABSTRACT FROM AUTHOR]

A systematic use of binary codes derived from the Hägg symbol are used to study close-packed polytypes. Seitz operators acting over the corresponding binary codes are defined and used. The number of non-equivalent polytypes of a given length are calculated through the use of the Seitz operators. The same procedure is applied to the problem of counting the number of polytypes complying with a given symmetry group. All counting problems are reduced to an eigenvector problem in the binary code space. The symmetry of the binary codes leads to the different space groups to which polytypes can belong. [ABSTRACT FROM AUTHOR]

Planar faulting in in rare earth - cobalt alloys with type structures Th2Ni17 and Th2Zn17 are studied. The structure changes from hexagonal for heavy rare earth to rhombohedral for light rare earth, all exhibiting different degrees of planar disorder. Faulting is quantitatively studied beyond the model of independent faulting events showing the strength of direct solutions to extract defects information from the diffraction patterns. It is showed that the analysis of the decaying term of the probability correlation function, does not only allow to quantify the loss of memory in the system through the correlation length but also, the strength of interaction between faults. The behavior of the decaying terms turns not to be of universal character when scaled against the correlation length and instead depends on the interaction of faulting. The reconstructive phase transition in this system seems to follow a path where the new phase appears within the disordered phase and grows without homogeneous reordering of the disordered arrangement. [ABSTRACT FROM AUTHOR]

A systematic use of binary codes derived from the Hagg symbol are used to study close-packed polytypes. Seitz operators acting over the corresponding binary codes are defined and used. The number of non-equivalent polytypes of a given length are calculated through the use of the Seitz operators. The same procedure is applied to the problem of counting the number of polytypes complying with a given symmetry group. All counting problems are reduced to an eigenvector problem in the binary code space. The symmetry of the binary codes leads to the different space groups to which polytypes can belong.