Structure of trisodium hexafluoromanganate(III) (original) (raw)
Related papers
A combined diffraction (XRD, electron and neutron) and electrical study of Na 3MoO 3F 3
Journal of Solid State Chemistry, 2003
Na 3 MoO 3 F 3 , a member of the A 2 BM VI O 3 F 3 family of elpasolite-related oxyfluorides, has been prepared by the reaction of NaF with MoO 3 at 650 C. It is shown by a combined X-ray, electron and neutron diffraction study, that the true symmetry of Na 3 MoO 3 F 3 is not monoclinic (pseudo-orthorhombic) as previously reported but instead triclinic (metrically rhombohedral) P1:
Structure of oxonium hexafluoroantimonate(V)
Acta Crystallographica Section B Structural Science, 1991
ALUMINATE SODALITES number of variables in a structure refinement. The following is based on Janner, Janssen & de Wolff (1983a,b). The diffraction pattern of tetragonal SAM, or SAW, can be divided unambiguously into sets of main reflections and of satellite reflections. Main reflections are those which become the cubic reflections above To. They correspond to a (pseudocubic) tetragonal I lattice. The main reflections are surrounded cuboctahedrally by satellite reflections (h +a, k, l+0), (h, k+a, 1+0). (h+a, k+a, l).
Inorganic Chemistry, 2000
Stoichiometric RMnO 3 perovskites have been prepared in the widest range of R 3+ ionic sizes, from PrMnO 3 to ErMnO 3. Soft-chemistry procedures have been employed; inert-atmosphere annealings were required to synthesize the materials with more basic R cations (R) Pr, Nd), in order to minimize the unwanted presence of Mn 4+. On the contrary, annealings in O 2 flow were necessary to stabilize the perovskite phases for the last terms of the series, HoMnO 3 , ErMnO 3 , and YMnO 3 , thus avoiding or minimizing the formation of competitive hexagonal phases with the same stoichiometry. The samples have been investigated at room temperature by high-resolution neutron powder diffraction to follow the evolution of the crystal structures along the series. The results are compared with reported data for LaMnO 3. The distortion of the orthorhombic perovskite (space group Pbnm), characterized by the tilting angle of the MnO 6 octahedra, progressively increases from Pr to Er due to simple steric factors. Additionally, all of the perovskites show a distortion of the MnO 6 octahedra due to the orbital ordering characteristic of the Jahn-Teller effect of Mn 3+ cations. The degree of orbital ordering slightly increases from La to Tb and then remains almost unchanged for the last terms of the series. The stability of the crystal structure is also discussed in light of bond-valence arguments.
Out-of-Center Distortions in d 0 Transition Metal Oxide Fluoride Anions
Inorganic Chemistry, 2002
Electronic effects and the bond network are the two factors that cause out-of-center distortions in octahedral d 0 transition metal oxide fluoride anions. Overlap between filled oxide p orbitals and vacant cation d orbitals results in strong, short metal−oxide bonds causing the metal ion to distort toward the oxide ligand. This primary, electronic distortion is not dependent on the extended structure. Smaller, secondary distortions of the anionic octahedra are caused by interactions with the bond network. [HNC 6 H 6 OH] 2 [Cu(NC 5 H 5 ) 4 (NbOF 5 ) 2 ], prepared with 5-hydroxy-2methylpyridine that provides two coordination contact sites to the anion when protonated, exhibits distortions in the anion reflecting both factors. Crystal data for [HNC 6 H 6 OH] 2 [Cu(NC 5 H 5 ) 4 (NbOF 5 ) 2 ]: monoclinic, space group C2/c (No. 15), with a ) 10.9427 Å, b ) 16.204(1) Å, c ) 21.396(2) Å, ) 93.263(1)°, and Z ) 4. Conditions for detection of both distortion types are discussed with five additional examples.
Redetermination of Na(3)TaF(8)
Acta crystallographica. Section C, Crystal structure communications, 2010
The crystal structure of trisodium octafluoridotantalate, Na(3)TaF(8), has been redetermined using diffractometer data collected at 153 K, resulting in more accurate bond distances and angles than obtained from a previous structure determination based on film data. The structure is built from layers running along [101], which are formed by distorted [TaF(8)] antiprisms and [NaF(6)] rectangular bipyramids sharing edges and corners. The individual layers are separated by eight-coordinated Na ions. Two atoms in the asymmetric unit are in special positions: the Ta atom is on a twofold axis in Wyckoff position 4e and one of the Na ions lies on an inversion centre in Wyckoff site 4d.
Journal of the Chemical Society, Dalton Transactions, 2002
The structure and bonding in bisaquamercury() trifluoromethanesulfonate, [Hg(OH 2 ) 2 (CF 3 SO 3 ) 2 ] ∞ , and trisaquathallium() trifluoromethanesulfonate, [Tl(OH 2 ) 3 (CF 3 SO 3 ) 3 ], have been studied by means of single-crystal X-ray diffraction, EXAFS and vibrational spectroscopy. The crystal structure of bisaquamercury() trifluoromethanesulfonate shows an unusual connectivity pattern. The mercury() ion strongly binds two water molecules axially with the Hg-O bond distance 2.11 Å, and four oxygen atoms from four trifluoromethanesulfonate ions complete a tetragonally compressed octahedral coordination geometry, at the mean Hg-O distance 2.53 Å. Two trifluoromethanesulfonate ions form double bridges between the bisaquamercury() entities giving rise to infinite >Hg(OH 2 ) 2 <(CF 3 SO 3 ) 2 >Hg(OH 2 ) 2 < chains. The parallel chains are held together in layers by relatively strong hydrogen bonds with O(-H) ؒ ؒ ؒ O distances in the range 2.688(9)-2.735(9) Å. The O-D stretching vibrational frequencies of the hydrogen bonds in the partly deuterated compound occur in a broad band at about 2400 cm Ϫ1 , bandwidth ca. 170 cm Ϫ1 . The layers are connected only via van der Waals interactions between the protruding CF 3 groups, consistent with the fragile sheet-like structure of the crystalline compound. Trisaquathallium() trifluoromethanesulfonate crystallises as molecular complexes where each thallium() ion binds three water molecules and three oxygen atoms from trifluoromethanesulfonate ions, with Tl-O bond distances in the range 2.18-2.24 Å. A hydrogen bond network between the water molecules and trifluoromethanesulfonate ions with O(-H) ؒ ؒ ؒ O distances in the range 2.65(1)-2.80(1) Å holds the structure together. Raman and infrared spectra have been recorded and analysed. The changes in force constants and vibrational frequencies have been correlated with bond lengths for the S-O bond in the coordinated trifluoromethanesulfonate ion and for the Hg-O and Tl-O bonds, also including the hexaaquaions in the comparisons.
Journal of Molecular Structure, 1990
The structure of gaseous trithiazyl trifluoride, [FSN]s, has been determined by electron diffraction. The molecule is found to conform to Csv symmetry, approximating closely the form it adopts in the crystalline solid, as well as the optimum structure calculated by ab initio methods. Salient parameters of the (re) structure are: r(S-F) = 161.9(0.4) and r(S-N) =159.2(0.2) pm; ~NSN=113.3(0.2), LSNS= 123.5(0.2), and LNSF=101.8(0.2) '. These and other features invite comparison with the geometries and dimensions of related S-N and S-F molecules.