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Structural and Vibrational Investigation of 2-Amino-5-nitropyridine. A Combined Experimental and Theoretical Studies

Oszust J., Baran J., Pietraszko A., Drozd M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 5

835-855

EN

The crystal structure of 2-amino-5-nitropyridine at low temperature was previously determined by other authors [1]. In this paper, the complementary X-ray study at ambient temperature is reported. The small differences in lattice parameters measurement in both experiments were found. The differential scanning calorimetric (DSC) measurements were performed. No phase transition was found in the temperature range 100–300 K. Additionally, the detailed vibrational spectroscopic analysis of 2-amino- 5-nitropyridine are reported. Powder infrared and Raman spectra of the title compound were measured at room temperature. The molecular structure of 2-amino-5-nitro pyridine has been calculated with the aid of density functional (B3LYP) method with the extended 6-311++G(d,p) basis set. The calculated geometrical parameters of investigated molecule in gas phase were compared with experimental X-ray data. The harmonic frequencies, potential energy distribution (PED) and IR intensities of 2-amino-5-nitro pyridine were calculated with B3LYP method. The assignment of the experimental spectra has been made as suming the calculated PED.

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Investigation of the Sc2Se3-Cu2Se-SnSe2 and Sc2Se3-Cu2Se-PbSe Systems at 870 K

Gulay L. D., Daszkiewicz M., Shemet V. Y., Pietraszko A.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 5

1001-1014

EN

Phase equilibria in the Sc2Se3-Cu2Se-SnSe2 and Sc2Se3-Cu2Se-PbSe sys tems at 870 K were determined using X-ray powder diffraction. The crystal structure of the ScCuSe2 (space group C2/m, a = 1.2762(3) nm, b = 0.7752(1) nm, c = 0.9260(1) nm, beta =133.32(2)°, R1 = 0.0396, wR2 = 0.1141) of the Sc2Se3-Cu2Se section was re investigated using X-ray single crystal diffraction. No compound exists in the Sc2Se3-SnSe2 section. The formation of the Cu2SnSe3 (Cu2GeS3 structure type, space group Cc) in the Cu2Se-SnSe2 sec tion was confirmed. The Sc2PbSe4 (CaFe2O4 structure type, space group Pnma) ex ists in the Sc2Se3-PbSe sec tion. No compound exists in the Cu2Se-PbSe section. The existence of the Sc0.96-1.18Cu0.37Sn1.19-1.02Se4 (Yb1.84Fe1.23S4 structure type, space group Fd3m, a = 1.0822-1.0935(2) nm) solid solution was established in the Sc2Se3-Cu2Se-SnSe2 sys tem. No quaternary compound exists in the Sc2Se3-Cu2Se-PbSe system.

3

Crystallization of (Th1-xUx)3As4 ferromagnetic semiconductor from the Ga flux

Wiśniewski P., Henkie Z., Pietraszko A.

Materials Science Poland

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2008

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Vol. 26, No. 4

933--938

EN

Crystals of n- or p-type heavily doped ferromagnetic semiconductor (Th1–xUx)3As4 (x = 0.67 and 0.80) were grown using a mineralization process in the Ga flux. An excess of As corresponding to MeAs2composition was necessary to grow the Me3As4 phase at temperature cycled between 1000 ºC and 1060 ºC. Dilution of U3As4 ferromagnet (Curie temperature TC = 198 K) with 20% of Th3As4 semiconductor (energy gap of 0.39 eV) reduced TC by 19%.

4

Investigation of the Ho2X3-Cu2X-ZX2 (X = S, Se; Z = Si, Ge) Systems

Lychmanyuk O., Gulay L., Olekseyuk L., Stępień-Damm J., Daszkiewicz M., Pietraszko A.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 3

353-357

EN

Phase equilibria in the Ho2X3-Cu2X-ZX2 (Z = Si, Ge; X = S, Se) systems at 870 K were determined using X-ray single crystal and powder diffraction. The existence of the HoCuS2, HoCu5 X4 compounds and the Ho(2+x)/3Cu2-xS2 (0 _ x _ 0.61), Ho(2+x)/3Cu2-xSe2 (0 _ x _ 1) solid solutionswas confirmed in theHo2X3-Cu2X (X=S, Se) systems. The Ho3Z1.25S7 compounds exist in the Ho2S3-ZS2 (Z = Si, Ge) systems. No compounds occur in the Ho2Se3-ZSe2 (Z = Si,Ge) systems. The formation of the Cu8ZX6, Cu4GeS4 and Cu2ZX3compounds was confirmed in the Cu2X-ZX2 (Z = Si,Ge;X= S, Se) systems. The formation of the Ho3CuZX7 (Z = Si, Ge; X = S, Se) compounds was observed in the Ho2X3-Cu2X-ZX2 systems.

5

Investigation of the Y2X3-Cu2X-SnX2 (X = S, Se) Systems

Shemet V., Gulay L., Stępień-Damm J., Pietraszko A., Olekseyuk L.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 6

943-955

EN

The interactions between the components in theY2X3-Cu2X-SnX2 (X = S, Se) systems at 870 K were determined using X-ray powder diffraction. The existence of the compound YCuS2 and the Y(2+x)/3Cu2-xS2 (0 x 0.52) solid solution was confirmed in the Y2S3-Cu2S section. The existence of the solid solution Y(2+x)/3Cu2-xSe2 (0 x 1) was confirmed in the Y2Se3-Cu2Se section. No compounds were found in the Y2S3-SnS2 and Y2Se3-SnSe2 sections. The formation of the compounds Cu4SnS4, Cu2SnS3, Cu4Sn7S16 in the Cu2S-SnS2 system and the Cu2SnSe3 compound in the Cu2Se-SnSe2 system was confirmed. The formation of the Y3Cu1-4xSn1+xS7 (0 x 0.09) solid solution and the Y2Cu0.20Sn0.95S5 compound was determined in the Y2S3-Cu2S-SnS2 system. The existence of the compound Y3CuSnSe7 in the Y2Se3-Cu2Se-SnSe2 system was confirmed.

6

Investigation of the Tm2Se3–Cu2Se–PbSe and Lu2Se3–Cu2Se–PbSe Systems at 870 K

Gulay L., Wołcyrz M., Pietraszko A., Olekseyuk I.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 10

1703-1714

EN

Phase equilibria in Tm2Se3–Cu2Se–PbSe and Lu2Se3–Cu2Se–PbSe systems at 870 K were investigated, using X-ray powder diffraction. R(2+x)/3Cu2-xSe2 (0 x 1) solid solutions (space group P3) were found in R2Se3–Cu2Se (R = Tmand Lu) sections of both systems. Crystal structure determinations for terminal RCuSe2 compositions of these solid solutions were performed. Er2/3Cu2S2 structure type was confirmed for TmCuSe2. LuCuSe2 crystallizes in the same structure, but with one extra position for Lu atoms. Crystal structures of R2PbSe4 (space group Pnma) in R2Se3–PbSe sections were determined usingX-single crystal and powder diffraction forR =Tmand Lu, respectively. The existence of R3.33CuPb1.5Se7 (Lu3.33CuPb1.5Se7 structure type, space group Cm), RCuPbSe3 (-BaLaCuSe3 structure type, space group Pnma) and Tm5CuPb3Se11 (Er5CuPb3Se11 structure type, space group Cmcm) compounds in R2Se3–Cu2Se-PbSe (R = Tm and Lu) systems was confirmed.

7

Structural phase transitions and their influence on Cu+ mobility in superionic ferroelastic Cu6PS5I single crystals

Gągor A., Pietraszko A., Drozd M., Połomska M., Kaynts D.

Materials Science Poland

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2006

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Vol. 24, No. 1

237--243

EN

The structural origin of Cu+ ion conductivity in Cu6PS5I single crystals is described in terms of structural phase transitions studied by X-ray diffraction, polarized light microscopy and calorimetric measurements. Below the phase transition temperature at Tc = (144-169) K, Cu6PS5I belongs to the monoclinic, ferroelastic phase, with the space group Cc. Above Tc, the crystal changes its symmetry to a cubic superstructure, with the space group F43c (a' = 19.528); finally, at 274 K, the disordering of Cu+ ions increases to the symmetry F43m (a = 9.794). The phase transition at 274 K coincides well with a strong anomaly in electrical conductivity observed on the Arrhenius plot. Diffusion paths for Cu+ ions are evidenced by means of atomic displacement factors and a split model. The influence of copper stoichiometry on Tc is also discu

8

Crystal Structure and Vibrational Studies of Glycine-LiNO3 and Glycine-NaNO3 Crystals

Baran J., Drozd M., Pietraszko A., Trzebiatowska M., Ratajczak H.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 11

1561-1577

EN

New crystal of glycine with lithium nitrate [(NN3 +CH2COO-)LiNO3; GLiN] was discovered. It belongs to the space group P1 of the triclinic system. Its structure is different from that of the glycine-NaNO3 crystal (GNaN). The Li2O6 units can be distinguished in the GLiN crystal. They have a shape of two symmetry related (through a centre of inversion) tetrahedrons with a common edge. Powder IR and FT-Raman spectra of GLiN and its deuterated analogue and of GNaN were measured and discussed with respect to the crystal structures. The splitting of some vibrations is observed, which suggests the breaking of the selection rules for the centre of inversion.

9

One-, Two- and Non-Coordinated Cr02- 4 Entity in the Nickel(II) Complexes. Structural and Spectroscopic Investigation

Pietraszko A., Bronowska W., Wojciechowska A., Staszak Z., Cieślak-Golonka M.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 2-3

309-324

EN

A systematic investigation of the chromate ion in [Ni(II)-(2,2_-bpy)-CrO4 2_ ] systems has been carried out. The effect of the Ni(II) ion and the organic ligand on the mode of the chromate position in the [Ni(bpy)3]CrO4_7.5H2O(1), [Ni(bpy)2(OCrO3)(H2O)]_5H2O(2) and catena-(ž-CrO4-O,O_)[Ni(bpy)(H2O)2]_2H2O (3) complexes has been shown. [Ni(bpy)3]CrO4_7.5H2O crystals (1) have a monoclinic symmetry with space group C2/c and 8 chemical units, forming a unit cell with a = 13.641(3) A, b = 22.939(5) A, c = 23.351(5) A and _ = 104.69(3) deg, whereas the [Ni(bpy)2(OCrO3)(H2O)]_5H2O crystals (2) have a monoclinic symmetry with space group P21/c and 4 chemical units per unit cell with a = 10.854(2) A, b = 22.665(5) A, c = 10.623(2) A and _ = 108.93(3) deg at room temperature. The chromate ion in 1 is not coordinated to the nickel(II) ion. The geometry around the Cr(VI) atom is pseudotetrahedral. Untypical for the chromate ion monodentate coordination has been found in the complex [Ni(bpy)2(OCrO3)(H2O)]_5H2O. The chromate position has been also elucidated from the digitally resolved IR spectra. The coordination of the chromate ion in 2 and 3 was also observed for the single crystal at 4K, in reflectance and solution electronic spectra through the appearance of a new transition at ca. 15000 cm-1. The full characterization of the chromophores present in the complexes: NiN6, NiN4O2, NiN2O4 and NiO6 have been obtained on the basis of the detailed analysis of the electronic spectra at 4K(Gaussian deconvolution followed by digital filtration).

10

Structural and vibrational studies of the molecular crystal formed by benzenamine with trifluoroacetic acid

Baran J., Barnes A. J., Barycki J., Pietraszko A., Ratajczak H.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

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Vol. 49, No. 2

115-124

EN

The crystal structure of benzenamine-trifluoroacetic acid has been found to belong to the P2i space group of the monoclinic system, with Z = 8, o = 10.294(2) A, b = 9.126(2) A, c = 20.603(4) A, and Beta = 98.77(3)°. In the crystal the amine is protonated and the resulting benzenammonium and trifluoroacetate ions are interlinked by a network of N—H- • -O hydrogen bonds. The observed infrared spectrum is in accordance with such a structure.

11

Crystal structure, thermal expansion, dielectric permittivity and phase transitions of Bi2S3

Łukaszewicz K., Stępień-Damm J., Pietraszko A., Kajokas A., Grigas J.

Polish Journal of Chemistry

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1999

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vol. 73 nr 3

541-546

EN

The crystal structure of Bi2S3 both natural (bismuthinite) and synthetic, reported in the literature, was determined at ambient temperature in the non-polar space group Pbnm. Physical properties of Bi2S3 indicate, however, on the possible phase transitions both in yhe high and low temperature regions. Precise lattice parameters measured as a function of temperature have shown weak anomalies at 160 and 410 K. The phase transition above 400 K has been also confirmed by measurements of microwave dielectric permittivity along the c-axis. The crystal structure of Bi2S3 has been determined at 130, 295 and 460 K. At all three temperature the crystal structure was successfully refined in the space group Pbnm. The weak phase transitions observed in Bi2S3 apparently do not change the symmetry, or these changes are too small to be deducted at the present level of accuracy of the X-ray crystal structure determination.