Neodymium ammonium hydroxynitrate, Nd(OH)2NO3.(NH4NO3)0.5.H2O, has been investigated by means of X-ray powder diffraction. Unit cell dimensions were determined by indexing programs, from diffractometer data obtained with strictly monochromatic CuKα1 radiation. An I orthorhombic cell was found: a = 24.577 (4) Å, b = 7.1488 (16) Å, c = 3.8211 (9) Å. It is shown that the h 1 1 reflections present a selective line broadening.

A new amine zinc hydroxide nitrate has been synthesized and investigated by means of X-ray powder diffraction. The monoclinic unit cell dimensions are a = 20.781(3) Å, b = 6.2151(9) Å, c = 5.4952(6) Å, β = 92.24(1)° (space group C2/m with Z = 2). The crystal structure has been refined by the Rietveld method using the structure of the related dihydrated phase as a starting model (Rp = 0.092 and RF = 0.068 for 372 reflections). The structure is characterized by octahedra [Zn(OH)6] describing a brucite-type layer, with one-quarter of the metal atoms missing, and by tetrahedra [Zn(OH)3(NH3)] located above and below the empty octahedra. The complex positive sheet has the formula [Zn3octa(OH)8Zn2tetra(NH3)2]2+ and the cohesion of the structure is realized through hydrogen bonding.

Powder-diffraction data were collected for a Chinese sample of ferrimolybdite. This mineral is orthorhombic, space group Pmmn or Pm21n, with a = 6.665(2), b = 15.423(5), c = 29.901(8), and V = 3074(1) Å3.

The effect of solid emulsifiers, added at the level of 10%, on the lattice parameters of tristearin and trilaurin, has been studied by powder X-ray diffraction method. The presence of sorbitan monostearate and glycerol-l-stearate affects slightly the lattice constant a in tristearin; on the other hand, although sorbitan monostearate causes an increase in a of trilaurin, glycerol-l-stearate does not. The presence of sorbitan monolaurate and glycerol-l-laurate affect a of trilaurin similarly to the long chain emulsifiers.

A correlation between the effect on a and the increase in melting point has been found.

The presence of the emulsifier does not alter drastically the lattice dimensions of the fat. The slight dissimilarity in crystal structure between tristearin and trilaurin is confirmed by the diverse effects of the emulsifiers on the internal structure of the fat.

The structure of [Pd(NH3)4]Cr2O7 has been determined ab initio from conventional X-Ray powder diffraction data by the Patterson method. The cell is monoclinic (space group P21/c, Z = 4), with a = 7.771(3) Å, b=11.578(1) Å, c=11.852(4) Å, and β= 105.50(4)°. Refinements of 57 parameters by the Rietveld method, using 852 reflections lead to RB = 0.032, RP = 0.075, and Rwp = 0.092. The structure is built up from PdN4 square planes linked to Cr2O7 groups by hydrogen bonds. Hydrogen atoms could not be located.

Standardized X-ray powder diffraction data for orthorhombic LaCo0.4Fe0.6O3 prepared by calcination of a glycine-nitrate combustion-synthesized precursor are reported. Orthorhombic unit cell parameters: a = 5.4688 (2), b = 5.5100 (2), c = 7.7462 (3) Å. The reference intensity ratio, I/Icor,= 6.12.

Indexed powder diffraction patterns and related crystallographic data are reported for tetracycline-urea tetrahydrate and tetracycline hexahydrate, neither of which is represented in the X-ray Powder Diffraction File. Objective evaluation of the data indicates high precision of d-spacings and unit-cell parameters, intensities that are acceptably reproducible, sensitivity for low intensity reflections, good resolution of closely spaced reflections, and close correspondence with calculated patterns.

Lattice thermal expansion of a number of compositions in the tetragonal (P4mm) single cell region of the lead zirconate titanate Pb(ZrxTi1−x)O3 system have been measured by high temperature X-ray diffraction. Polynomial coefficients which describe the temperature dependence of the lattice constants of each composition below and above the ferroelectric-paraelectric transition temperature are given.

The lattice parameters of triammonium citrate, (NH4)3C6H5O7, were determined by X-ray single crystal and powder diffraction methods. The crystal structure is orthorhombic with a = 6.187 ± 0.001 Å, b = 14.803 ± 0.004 Å, and c = 10.826 ± 0.003 Å, and from the systematic absences, the space group is Pcc2 ().