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The reinvestigation of tetrazene single crystalline material by means of X-ray methods resulted in a slightly different structure when compared to previously published data. Reaction conditions responsible for different crystalline modification formation were investigated. Newly described C form was found to be the primary reaction product and the combined action of temperature and the presence of water over time is required for the transition to the A form. Both forms were described by X-ray powder diffraction. Tetrazene was also subjected to infrared and Raman spectroscopy, which allowed differentiating between the forms. The molecule was isotopically labeled with 15N atoms at two different locations (ring and nitrogen sidechain) and employed in assigning vibrational modes to the resulting bands. Differences between sensitivities to mechanical stimuli of the two modifications were investigated and found industrially insignificant. In the same vein, the performance of either modification in primer composition and primer was identical. Opětovné zkoumání tetrazenového monokrystalu pomocí rentgenových metod vedlo k mírně odlišné struktuře ve srovnání s dříve publikovanými údaji. Byly zkoumány reakční podmínky zodpovědné za odlišný vznik krystalických modifikací. Bylo zjištěno, že nově popsaná forma C je primárním reakčním produktem a pro přechod na formu A je nutné kombinované působení teploty a přítomnosti vody v čase. Obě formy byly popsány pomocí rentgenové práškové difrakce. Tetrazen byl rovněž podroben infračervené a Ramanově spektroskopii, což umožnilo formy rozlišit. Molekula byla izotopicky značena atomy 15N na dvou různých místech (kruh a postranní dusíkatý řetězec) a využita při přiřazování vibračních módů výsledným pásům. Byly zkoumány rozdíly mezi citlivostí obou modifikací na mechanické podněty, které byly shledány jako průmyslově nevýznamné. Podobně pak byla i funkčnost obou modifikací v zápalkových složích a zápalkách identická.

X-ray powder diffraction data, unit-cell parameters, and space group for a new memantine analogue of a Platinum (Pt) (II) complex labelled LA-13, C12H24Cl2N2Pt, are reported [a = 8.324(1) Å, b = 27.838(2) Å, c = 7.113(1), β = 111.25(1), unit-cell volume V = 1536.26 Å3, Z = 4, and space group P21/n]. All measured lines were indexed and are consistent with the P21/n space group. No detectable impurity was observed.

X-ray powder diffraction data, unit-cell parameters, and space group for acetamidinium formate, C3H8N2O2, are reported [a = 6.4564(5) Å, c = 13.021 (3) Å, unit-cell volume V = 542.8(3) Å3, M.p. = 215(1)°C, ρc = 1.274 g.cm−3, ρm = 1.269 g.cm−3, Z = 4, and space group P43212]. The front-loaded technique got sample with strong preferred orientation because of plate-like shape of crystallites, so the capillary packing was used for final powder data collection. All measured lines were indexed and are consistent with the P43212 space group. No detectable impurities were observed.

X-ray powder diffraction data, unit-cell parameters and space group for 2-(ethylamino)-2-(3-methoxyphenyl)cyclohexan-1-one hydrochloride, C15H22ClNO2, are reported [a = 8.574(2) Å, b = 9.943(2) Å, c = 8.774(1) Å, β = 100.294(3)°, unit-cell volume V = 736(1) Å3, Z = 2, and space-group P21]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurities were observed.

X-ray powder diffraction data, unit-cell parameters, and space group for S-2-(methylamino)-2-phenylcyclohexan-1-one hydrochloride, C13H18ClNO, are reported [a = 6.578 (1) Å, b = 13.250 (2) Å, c = 15.096 (2) Å, β = 91.619 (3)°, unit-cell volume V = 1315(1) Å3, Z = 4, and space group P21]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurities were observed.

X-ray powder diffraction data, unit-cell parameters and space group for C8H20CuN10O8 are presented [a = 5.262 (2) Å, b = 14.051 (3) Å, c = 12.183 (3) Å, β = 96.912 (5)°, unit-cell volume V = 894.3 Å3, Z = 2, space group P21/n]. All measured lines were indexed and are consistent with the P21/n space group. No detectable impurities were observed.

X-ray powder diffraction data, unit cell parameters, and space group for a new platinum-based anticancer complex cis-[bis(acetonitrile)]-[(1R,2R)-1,2-diaminocyclohexane-κN, κN′]platinum (II)nitrate (1:2) monohydrate, cis-[Pt(C2H3N)2(C6H14N2)](NO3)2·H2O, are presented [a=12.638(3) Å, b=12.153(2) Å, c=11.881(3) Å, β=95.145(4)°, space group P21, cell volume=1817.5 Å3, and Z=4]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurities were observed.

Simvastatin is a substance used for the treatment of hypercholesterolemia. In addition to the already known room temperature structure of simvastatin (Cejka et al. in Acta Cryst C59:o428, 2003) two new low-temperature polymorphs were found by X-ray powder diffraction with the phase transition at 261 and 223 K (later confirmed by DSC to be 272 and 232 K). The main differences among three polymorphs consist in the side-chains conformation only and the phase changes are fully reversible. The structures of the polymorphs were studied by the powder diffraction based on synchrotron radiation as well as by solid-state NMR spectroscopy.

Leucite based ceramic materials are being a subject of an extensive scientific interest in recent years, especially in a field of dental prosthesis. Ceramic structures are used to replace missing teeth, tooth structure lost to disease or trauma, and unaesthetic, but otherwise healthy, tooth enamel [1]. The significant attributes of dental ceramics are its aesthetical (it can be coloured to closely resemble teeth it must replace) and chemical (stability toward oral flora and corrosive components of foods and saliva) qualities. The presence of leucite, exhibiting high values of a thermal expansion coefficient, in a porcelain matrix enables its fusion to metal reinforcement and so to achieve high mechanical strength. In addition in last few years it was hypothesized that leucite thanks to its phasetransition behaviour could potentially toughen leucite-glass (porcelain) systems and so lead to dental materials having high fracture toughness [2].

X-ray powder diffraction data, unit-cell parameters, and space group for a new bis(β-diiminato) Cu(II) complex, C44H54CuN4O4, are reported [a = 8.683(3) Å, b = 11.216(3) Å, c = 11.753(4) Å, α = 66.27(3), β = 84.61(3), γ = 78.85(3), unit-cell volume V = 1027.77 Å3, Z = 1, and space group P-1]. All measured lines were indexed and are consistent with the P-1 space group. No detectable impurity was observed.

X-ray powder diffraction data, unit-cell parameters, and space group for a new Ru Cl diamide complex, C36H48N2SO3RuCl, are reported [a = 12.487(4) Å, b = 16.624(5) Å, c = 17.230(3) Å, unit-cell volume V = 3576,79 Å3, Z = 4, and space group P212121]. All measured lines were indexed and are consistent with the P212121 space group. No detectable impurity was observed.

X-ray powder diffraction data, unit-cell parameters, and space group for a novel platinum-based anticancer complex, Pt(C6H10N2)Br2, are presented [a = 10.049 (1) Å, b = 9.240 (2) Å, c = 11.497 (2) Å, β = 101.945 (3)°, unit-cell volume V = 1044.41 Å3, Z = 4, and space group P21/c]. All the measured lines were indexed and are consistent with the P21/c space group. No detectable impurities were observed.

X-ray powder diffraction data, unit-cell parameters, and space group for a novel platinum-based anticancer complex cis-[dibromo(1R,2R)-1, 2-diaminocyclohexane-κN, κN′]platinum(II), cis-Pt(C6H14N2)Br2, are presented [a = 11.862(4) Å, b = 7.222(3) Å, c = 13.353(2) Å, β = 97.813(7)°, cell volume V = 1133,36 Å3, Z = 4, space group P21]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurities were observed.

X-ray powder diffraction data, unit-cell parameters, and space group for a new succinylcholine iodide polymorph II, C14H30O4N2I2, are reported [a=13.908(3) Å, b=13.184(3) Å, c=11.717(2) Å, β=92.501(3)°, unit-cell volume V=2146,28 Å3, Z=4, space group P21/c]. All measured lines with the exception of one were indexed and are consistent with the P21/c space group. No detectable impurities were observed.

X-ray powder diffraction data, unit-cell parameters and space group for the β-form of pigment yellow 181, C25H21N7O5, are reported [a= 22.556(6) Å,b= 4.9684(9) Å,c= 21.318(6) Å,β= 109.492(4)°, unit-cell volumeV= 2252,1 Å3,Z= 4, space groupP21/c]. All measured lines were indexed and are consistent with theP21/c space group. No detectable impurities were observed.

X-ray powder diffraction data, unit cell parameters, and space group for alaptide are presented (a=21.136(4) Å, b=7.212(4) Å, c=6.126(3) Å, space group P212121, cell volume=933.8(8) Å3, and Z=4). All measured lines were indexed and are consistent with the P212121 space group. No detectable impurities were observed.

X-ray powder diffraction data, unit-cell parameters and space group for a new chiral Kemp’s acid diamide, C18H28N2O3, are reported [a = 12.456(2) Å, b = 12.471(2) Å, c = 12.088(2) Å, β = 99.003(2)°, unit-cell volume V = 1854,48 Å3, Z = 4, space group P21]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurity was observed.

High-level radioactive wastes can be safely immobilized in alkali-aluminoborosilicate glass. To reduce the cost of the vitrification process, the waste loading should be maximized. This can be done by optimizing the process using mathematical modeling. The main objective of our work was to determine one of the necessary inputs for the mathematical model, which is the effect of temperature and composition on the concentration of spinel crystals and their size. We prepared six glasses with a different content of Li+, Na+, Mg2+, Ni2+, Cr3+, and SiIV and studied the effect of composition on the temperature dependence of spinel equilibrium concentration in glass by X-ray powder diffraction. The size of crystals was determined using optical microscopy. It was found that the temperature effect on spinel concentration significantly increased as the content of Ni2+ or Mg2+ in glass increased and slightly decreased as the content of Cr3+ increased and Li+ and Na+ content decreased. Both Ni2+ and Cr3+ acted as nucleating agents, producing a huge number of tiny spinel crystals (∼2 μm). In particular, Ni2+ seems to very significantly facilitate spinel crystallization.

Metergoline is a dopamine agonist and serotonin antagonist used both in human and veterinary medicine. In addition to the previously known crystalline form, a new polymorph, which crystallizes from aqueous solution, was found. Since it was initially impossible to prepare a single crystal of quality suitable for single crystal X-ray diffraction measurements using a conventional laboratory source, the structure was solved from the powder diffraction data using synchrotron radiation. The structure determination also included solving the effects of preferred orientation. Characterization was simultaneously done by solid-state NMR spectroscopy. Finally, a small single crystal suitable for synchrotron diffraction was found after numerous tries. Crystal structure determination using this single crystal confirmed the powder-based solution. Comparison of information obtained by different experimental methods (powder diffraction, ssNMR, single crystal diffraction) was made.