Structural studies of technetium complexes. III. The crystal structure of Tris[2-aminobenzenethiolato(2 - )-S, N]technetium(VI) : a trigonal-prismatictechnetium geometry

1982 ◽  
Vol 35 (12) ◽  
pp. 2413 ◽  
Author(s):  
J Baldas ◽  
J Boas ◽  
J Bonnyman ◽  
MF Mackay ◽  
GA Williams

Tris[2-aminobenzenethiolato(2–)-S,N]technetium(VI), Tc(NHC6H4S)3, has been prepared by the reaction of ammonium pertechnetate with 2-aminobenzenethiol in 0.1 M hydrochloric acid solution at room temperature. The crystal structure of Tc(NHC6H4S)3 has been determined by single-crystal X-ray diffraction methods at 17�C. Crystals are orthorhombic, space group P212121, with a 10.696(2), b 11.363(1), c l5.220(2) �, and Z 4. Automatic diffractometry has provided significant Bragg intensities for 1413 independent reflections, and the structure of the correct enantiomorph has been refined by full-matrix least-squares methods to R 0.044. The compound, which is isostructural with the molybdenum analogue, consists of discrete molecules of Tc(NHC6H4S)3. The environment about the technetium atom closely approximates a trigonal-prismatic geometry. This is the first example where this geometry has been established with technetium. Differences in detail between the structures of TC(NHC6H4S)3 and its molybdenum analogue are discussed. In particular the S3N3 coordination polyhedron in TC(NHC6H4S)3is contracted and the distortions from ideal trigonal-prismatic geometry are less than in the molybdenum analogue.

2021 ◽  
pp. 2150407
Author(s):  
S. I. Ibrahimova

The crystal structure and thermal properties of the [Formula: see text] compound have been investigated. Structural studies were performed by X-ray diffraction at room temperature. The crystal structure of this compound was found to correspond to the hexagonal symmetry of the space group P61. Thermal properties were studied using a differential scanning calorimetry (DSC). It was found in the temperature range [Formula: see text] that thermal effects occur at temperatures [Formula: see text] and [Formula: see text]. The thermodynamic parameters of these effects are calculated.


1984 ◽  
Vol 37 (4) ◽  
pp. 751 ◽  
Author(s):  
J Baldas ◽  
J Bonnyman ◽  
MF Mackay ◽  
GA Williams

Dichlorobis(diethyldithiocarbamato)thionitrosyltechnetium(III), [Tc(S2CNEt2)2Cl2(NS)], has been prepared by the reaction of [Tc(S2CNEt2)2N] with either disulfur dichloride or thionyl chloride. The crystal structure of [TC(S2CNEt2)2Cl2(NS)] has been determined by single-crystal X-ray diffraction methods at 15�C. Crystals are orthorhombic, space group Pcmn, with a 8.936(1), b 15.681(1), c 28.445(7) �, and Z 8. Automatic diffractometry has provided significant Bragg intensities for 2078 independent reflections, and the structure has been refined by full-matrix least-squares methods to R 0.078. The crystal lattice is disordered across a non-crystallographic mirror plane, the degree of disorder being 4.0(2)% for the crystal described above, and 21.9(7)% for another crystal initially used to obtain an intensity data set. There are two independent molecules of [Tc(S2CNEt2)2Cl2(NS)] in the asymmetric unit, and in each the technetium atom is seven-coordinate with a pentagonal-bipyramidal coordination environment. The Tc=N=S bonding is linear with Tc=N c. 1.75 and N=S c. 1.52 �, which indicates that the thionitrosyl group is a three-electron donor with a formal positive charge. This is only the third crystal structure of a complex containing the thionitrosyl group to be determined, and the first for technetium.


Author(s):  
E. Louise R. Robins ◽  
Michela Brunelli ◽  
Asiloé J. Mora ◽  
Andrew N. Fitch

AbstractDSC and high-resolution powder X-ray diffraction measurements in the range 295 K–100 K show that RS-thiocamphor undergoes two phase transitions. The first, at around 260 K on cooling, is from the room-temperature body-centred-cubic phase to a short-lived intermediate. At 258 K the low-temperature form starts to appear. The crystal structure of the latter is orthorhombic, space group


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Suresh Sharma ◽  
B. D. Gupta ◽  
Rajni Kant ◽  
Vivek K. Gupta

The structure of title compound Negundoside (2′-p-hydroxybenzoyl mussaenosidic acid) was established by spectral and X-ray diffraction studies. The compound crystallizes in the monoclinic crystal system with space group P21 having unit cell parameters: a=11.6201 (5) Å, b=9.2500 (4) Å, c=12.2516 (5) Å, β=97.793 (4)°, and Z=2. The crystal structure was solved by direct method using single crystal X-ray diffraction data collected at room temperature and refined by full-matrix least-squares procedures to a final R value of 0.0520 for 3389 observed reflections.


2017 ◽  
Vol 72 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Daniela Vitzthum ◽  
Michael Schauperl ◽  
Klaus R. Liedl ◽  
Hubert Huppertz

AbstractOrthorhombic In3B5O12 was synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 12.2 GPa and 1500°C. Its structure is isotypic to the rare earth analogs RE3B5O12 (RE=Sc, Er–Lu). In the field of indium borate chemistry, In3B5O12 is the third known ternary indium borate besides InBO3 and InB5O9. The crystal structure of In3B5O12 has been determined via single-crystal X-ray diffraction data collected at room temperature. It crystallizes in the orthorhombic space group Pmna with the lattice parameters a=12.570(2), b=4.5141(4), c=12.397(2) Å, and V=703.4(2) Å3. IR and Raman bands of In3B5O12 were theoretically determined and assigned to experimentally recorded spectra.


1978 ◽  
Vol 31 (2) ◽  
pp. 411 ◽  
Author(s):  
GR Scollary

A structural analysis of [(η-C5H5)2YMe2AlMe2] has been carried out by X- ray diffraction. Crystals are orthorhombic, space group Pna21, a 17.969(6), b 7.988(4), c 10.870(4) Ǻ, Z 4. The structure has been refined by a full-matrix least-squares procedure to R 0.052 for 663 observed reflections (Mo Kα automatic diffractometry). The structure contains a dimethyl bridge, the average bridging bond distances being 2.58(3) Ǻ for Y-C and 2.10(2) Ǻ for Al-C, and the Y-Al separation is 3.056(6) Ǻ.


1987 ◽  
Vol 40 (1) ◽  
pp. 27 ◽  
Author(s):  
GA Williams ◽  
J Bonnyman ◽  
J Baldas

The crystal structure of [AsPh4]2 [ Tc (NCS)6].CH2Cl2 has been determined by single-crystal X-ray diffraction methods at 23 � 1�C . Crystals are tetragonal, space group I4/m, with a 11.523(5), c 22.43(2) �, and Z 2. Diffraction data from two different crystals were analysed and in both cases disorder was present in the crystal lattices. Full-matrix least-squares refinement gave a final R value of 0.073 for 1188m independent reflections. The [TC(NCS)6]2- anion has an octahedral structure with the technetium(1V) atom situated on a site of 4/m symmetry. The Tc -N bond lengths are 2.00(1) and 2.01(1) Ǻ with N- Tc -N angles of exactly 90�. Two of the Tc -NCS groups are constrained by the crystal symmetry to be perfectly linear, while for the remaining four Tc -NCS groupings the Tc -N-C and N-C-S angles are 175.9(9)� and 175.3(10)� respectively.


1989 ◽  
Vol 42 (6) ◽  
pp. 875 ◽  
Author(s):  
GA Williams ◽  
J Baldas

The crystal structure of [AsPh4]2 [ TcN(mnt)2] ( mnt = 1,2-dicyanoethenedithiolate) has been determined by single-crystal X-ray diffraction methods at 21 � 1 C. Crystals are monoclinic, space group Pn , with a 11 369(2), b 15.530(2), c 14.421(3) � , P 97.58(2)�, and Z 2. Full-matrix least-squares refinement gave a final R value of 0.057 for 4232 independent reflections. The technetium atom in the [TcN( mnt )2]2- anion has square-pyramidal coordination geometry with the nitrido ligand in the apical position, Tc =N 1.59(1) � , and four Tc -S bonds with distances varying between 2.367(4) and 2.419(4) �. The Tc =N core is disordered about a pseudo-inversion centre, but unequal occupancies of the disordered sites preclude a centrosymmetric structure.


1984 ◽  
Vol 37 (5) ◽  
pp. 1111 ◽  
Author(s):  
PC Healy ◽  
JM Patrick ◽  
AH White

The crystal structure of the title compound, [Cu(OH2)2(phen)] (SO4) (phen = 1,10-phenanthroline), has been determined by single-crystal X-ray diffraction methods at room temperature, being refined by full matrix least-squares methods to a residual of 0.033 for 1445 'observed' reflections. Crystals are monoclinic, C2/c, a 14.883(8), b 13.843(9), c 7.019(4) �, β 108.60(4)�, Z 4. As in a number of other copper(II) and nickel(II) derivatives with (CuL4)(SO4) stoichiometry, the pseudo-square planar copper environments [Cu-N,O: 2.009(2), 1.970(2) � in the present case] are bridged through the two axial coordination positions by sulfate groups: O.SO2.O[Cu(OH2)2(phen)]O.SO2.0, etc. to give a linear polymeric array [Cu-O(SO4), 2.468(3) �]; a crystallographic twofold axis passes through the copper atom.


1979 ◽  
Vol 32 (2) ◽  
pp. 297
Author(s):  
BW Skelton ◽  
AH White

The crystal structure of the title compound, NaAg(NO2)2, has been determined by single-crystal X-ray diffraction at 295(1) K and refined by full-matrix least squares to a residual of 0.043 for 449 'observed' reflections. Crystals are orthorhombic, space group Fd2d, a 7.913(2), b 10.721(2), c 10.857(3) �, Z 8. The structure is closely related to that of sodium and silver nitrites; the silver environment is dominated by the 'linear' coordination of a nitro group (Ag-N 2.25(2) �) and a 'chelating' pair of oxygen atoms from another NO2- species (Ag-O 2.422(8)�), the O2N-Ag-O2N group containing a crystallographic 2 axis.


Sign in / Sign up

Export Citation Format

Share Document