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O Bond Distances (o + bond_distance)

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Chemistry100%

Selected Abstracts

,-Oxo-bis­[(2,3,12,13-tetra­bromo-5,10,15,20-tetra­phenyl­porphyrinato)­iron(III)] bis­(di­chloro­methane) solvate

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2000
Ming Li
The precise structure of the title compound, [Fe2O(C44H24Br4N4)2]·2CH2Cl2, is reported. The Fe,N distances are non-equivalent in pairs because of the asymmetric peripheral substitution; the values are 2.098,Å to the brominated rings and 2.041,Å to the other two rings. The Fe,O bond distance is 1.7583,(4),Å. The mol­ecule has required twofold symmetry so that there is one unique porphyrin macrocycle and one Fe,O bond length in contrast to a previous report on the same species. [source]

Structural stability and formability of ABO3 -type perovskite compounds

ACTA CRYSTALLOGRAPHICA SECTION B, Issue 6 2007
Huan Zhang
On the basis of the bond-valence model (BVM) and structure-map technology, the structural stability and formability of ABO3 -type perovskite compounds were investigated in 376 ABO3 -type compounds. A new criterion of structural stability for ABO3 -type perovskite compounds has been established by the bond-valence calculated tolerance factors, which are in the range 0.822,1.139. All global instability indices for ABO3 -type perovskite compounds are found to be less than 1.2,v.u. (valence units) and increase with a decrease in oxidation state of the B cations (i.e. structural stability in the formation of an ideal cubic perovskite follows the order A+B5+O3 -type > A2+B4+O3 -type > A3+B3+O3 -type). Three new two-dimensional structure maps were constructed based on the ideal A,O and B,O bond distances derived from the BVM. These maps indicate the likelihood of particular perovskite compounds being formed. The present work enables novel perovskite and perovskite-related compounds to be explored by screening all the possible elemental combinations in future crystal engineering. [source]

Le phosphate de cobalt et de lithium à valence mixte Li4+xCo2,x(P2O7)2 (x = 0,03): étude structurale et analyse de distribution de charge

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2010
Salah Kouass
The title compound, namely lithium cobalt(II/III) bis(diphosphate), Li4.03Co1.97(P2O7)2, is a new mixed-valent lithium/cobalt(II/III) phosphate. Three metal sites out of seven are occupied simultaneously by Li+ and CoII/III ions. This disorder was established both from an analysis of the atomic displacement ellipsoids and Li/Co,O bond distances, and by means of a charge-distribution (CHARDI) model, which provides satisfactory agreement on the computed charges (Q) for all the cations. [source]

The cyclic vanadylacetate (C24H20P)[V4O8(C2H3O2)4(NO3)]

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 1 2000
Dirk Wulff-Molder
In the title complex, tetraphenylphosphonium ,4 -nitrato-,4O - cyclo -tetrakis(,-acetato- O:O,)tetra-,-oxo-tetrakis[oxovana-dium(V)], the anion lies about a twofold axis and consists of the cyclic [V4O8] unit coordinated by four acetato ligands with interatomic V,V distances of 3.269,(1) and 3.273,(1),Å. The double-bonded O atom [N=O 1.102,(6) and N,O 1.268,(4),Å] of the nitrato ligand links the four V atoms with V,O bond distances of 2.613,(2) and 2.813,(2),Å. The negative charge of the complex is balanced by tetraphenyl­phosphonium cations occupying the Na positions in the NaCl-type ionic packing of the structure. [source]