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1.
Tomasz Stawski Janusz Szklarzewicz Krzysztof Lewiński 《Transition Metal Chemistry》2006,31(3):353-361
The single crystal X-ray structure of (AsPh4)[W(bpy)(CN)6] is described. The structure of octa- and hepta-coordinated intermediates of substitutional photolysis of [Mo(CN)8]4− ion in aqueous media were determined by performing semi-empirical calculations. On the basis of obtained results as well
as on empirical data the photolysis scheme has been postulated. 相似文献
2.
Szklarzewicz Janusz Samotus Alina Nowicka Beata Burgess John Fawcett John Russell David R. 《Transition Metal Chemistry》1999,24(2):177-182
The X-ray crystal structure of (bpyH2)2[W(CN)8]·4H2 O (bpyH2=2,2-bipyridinium) is described. The [W(CN)8]4– anion has an approximately square antiprismatic (D4d) conformation, seemingly imposed by strong anion–water–cation hydrogen-bonding interactions. Bond distances in the anion are: WC 2.150(5), 2.163(5); CN 1.128(6), 1.145(6)Å and the angles WCN are 177.6(5), 178.3(5)°. The dihydrate and the anhydrous salt are both intensely black solids, exhibiting ion-pair charge-transfer interaction between cation and anion. E.s.r. spectra indicate that 30% of the tungsten is present as WV in the solid state, but that in solution only the WIV complex is present. The electron withdrawing effect of the cation is discussed and compared with that in a series of salts with different bipyridinium cations. 相似文献
3.
Edward Mikuli Marta Liszka-Skoczylas Joanna Hetmańczyk Janusz Szklarzewicz 《Journal of Thermal Analysis and Calorimetry》2010,102(3):889-897
[Mn(NH3)6](NO3)2 crystallizes in the cubic, fluorite (C1) type crystal lattice structure (Fm \( \overline{3} \) m) with a = 11.0056 Å and Z = 4. Two phase transitions of the first-order type were detected. The first registered on DSC curves as a large anomaly at T C1 h = 207.8 K and T C1 c = 207.2 K, and the second registered as a smaller anomaly at T C2 h = 184.4 K and T C2 c = 160.8 K (where the upper indexes h and c denote heating and cooling of the sample, respectively). The temperature dependence of the full width at half maximum of the band associated with the δs(HNH)F1u mode suggests that the NH3 ligands in the high temperature and intermediate phase reorientate quickly with correlation times in the order of several picoseconds and with activation energy of 9.9 kJ mol?1. In the phase transition at T C2 c probably only a some of the NH3 ligands stop their reorientation, while the remainders continue to reorientate quickly with activation energy of 7.7 kJ mol?1. Thermal decomposition of the investigated compound starts at 305 K and continues up to 525 K in four main stages (I–IV). In stage I, 2/6 of all NH3 ligands were seceded. Stages II and III are connected with an abruption of the next 2/6 and 1/6 of total NH3, respectively, and [Mn(NH3)](NO3)2 is formed. The last molecule of NH3 per formula unit is freed at stage IV together with the simultaneous thermal decomposition of the resulting Mn(NO3)2 leading to the formation of gaseous products (O2, H2O, N2 and nitrogen oxides) and solid MnO2. 相似文献
4.
Nowicka Beata Burgess John Parsons Simon A. Samotus Alina Szklarzewicz Janusz 《Transition Metal Chemistry》1998,23(3):317-319
Solvatochromism of the [Mo(CN)3O(phen)]− ion has been studied. Solvent effects on pressure dependence (up to 1.25 kbar) of wavelengths of maximum absorption for charge-transfer
bands of several molybdenum(IV) and tungsten(IV) complexes, [M(CN)3O(diimine)]− (M = Mo or W), are described. The effects of applied pressure are larger for less polar unstructured solvents than for highly
polar hydrogen-bonded solvents.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
The kinetics of the reaction between the protonated species of trans-[Mo(CN)4O2]4– and salicylaldehyde (Hsal) was studied in the 7.8–12.0 pH range in H2O-MeOH mixtures. Spectroscopic characterization of the product indicates that the aqua and cyano ligands are substituted by sal– with formation of the [Mo(CN)3O (sal- 2O,O)]2– ion. The formation quotient, Kf for the overall reaction=31 (±1) at 25°C. In the presence ofan excess of ligand, the rate law is of the formd[Mo(CN)3O(sal- 2O,O)2–]/dt =kobs[Mo(CN)4O (H2O)2–]. The kobs value is equal to 2.9 (±8)×10–3 at 25°C. The activation parameters H (kobs) and S (kobs) are 103 (±9)kJmol–1 and 45 (±8)JK–1mol–1, respectively. The amount of the product formed decreases with increasing pH but the rate of the product formation increases. The reaction mechanism and the possible formation of Schiff base ligands in the presence of amines are discussed. 相似文献
6.
Patrycja Paciorek Janusz Szklarzewicz Wojciech Nitek 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):513-516
In the title complex salt, (C6H6N5)2[ZnCl4], the ZnII cation is coordinated by four chloride ligands in a distorted tetrahedral geometry. The organic cations and complex anions are connected by N—H...Cl hydrogen bonds, leading to the formation of a three‐dimensional network. The title complex salt was synthesized by the reaction of sodium azide, pyridine‐2‐carbonitrile and ZnCl2 in aqueous solution. The salt was characterized by elemental analysis and IR and UV–Vis spectroscopy. 相似文献
7.
Szklarzewicz Janusz Jurowska Anna Hodorowicz Maciej Kazek Grzegorz Mordyl Barbara Menaszek Elżbieta Sapa Jacek 《Transition Metal Chemistry》2021,46(3):201-217
Transition Metal Chemistry - Twenty-four oxidovanadium(IV,V) complexes with tridentate Schiff base ligands based on 5-nitrosalicylaldehyde, 5-methoxysalicylaldehyde, or 5-sulfosalicylaldehyde and... 相似文献
8.
PPh4]3[W(CN)7(O2)].4H2O as the representative of the [M(L)7(LL)] class for nine-coordinate complexes
The photoinduced dissociation of a W-CN bond in [W(CN)8]4- in an aqueous solution under ambient conditions, in conjunction with the uptake of molecular oxygen, affords the W(VI) mixed-ligand complex anion [W(CN)(7)(eta2-O2)]3-, conveniently isolable as its [PPh4+] salt. Although research into the chemistry of cyanomolybdates and cyanotungstates has been pursued with great interest and vigor over several decades, there is a paucity of structurally characterized cyano-peroxo complexes of Mo and W. The side-on coordination mode of the peroxo moiety in [W(CN)7(eta2-O2)]3- has been ascertained with X-ray crystal structure determination [d(O-O) = 1.41 A; peroxo bite angle: 41.0 degrees ] and corroborated with vibrational spectroscopy [nu(O-O) = 915 cm(-1)]. The complex ion exhibits trapezoidal tridecahedral geometry and represents the new class of nine-coordinate complexes with one bidentate and seven monodentate ligands. Cyclic voltammetry shows a reversible redox behavior of [W(CN)7(eta2-O2)]3- in CH3CN with its standard reduction potential equal to 1.130 V. Generally, interest in atmospheric oxygen derives from the versatility of this molecule as a ligand and oxidant and extends to the physicochemical features it imparts to transition metals such as copper and iron in biological oxygen carriers. 相似文献
9.
[Mo(CN)4O(H2O)]2– reacts with hydrazine and salicylaldehyde in aqueous solution to give [Mo(CN)3O(salhy)]2– (Hsalhy = salicylaldehydehydrazone), isolated as green (Ph4P)2[Mo(CN)3O(salhy)] · 6H2O. In CHCl3, the product converts within seconds into (Ph4P)2[Mo(CN)3O(salhy)] · H2O · 2CHCl3 yielding microcrystals having a metallic golden sheen. The complexes were characterised by elemental analysis, t.g. and d.t.a., u.v.–vis. absorption, i.r., 1H-n.m.r. spectroscopy and by magnetic susceptibility measurements. The visible spectra in various solvents are dominated by the metal-to-ligand charge-transfer bands with absorption maxima linearly dependent on the Reichardt E
T
parameter. In halogenated alkanes, the unusual hipsochromic band shift is interpreted in terms of possibile solvent bonding to the metal centre. Cyclic voltammetry indicates that the salt undergoes reversible one electron oxidation with E
1/2 = –0.473 V in DMSO versus ferrocene. 相似文献
10.
Piotr Zabierowski Janusz Szklarzewicz Wojciech Nitek 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):659-661
The title compound, [Cu(C9H8BrClNO2)2], is a square‐planar complex. The potentially tridentate dibasic 2‐bromo‐4‐chloro‐6‐{[(2‐hydroxyethyl)imino]methyl}phenolate ligand coordinates in a trans‐bis fashion to the CuII centre via the imine N and phenolate O atoms. The CuII atom lies on the centre of inversion of the molecule. The potentially coordinating hydroxyethyl group remains protonated and uncoordinated, taking part in intermolecular hydrogen bonds with vicinal groups, leading to the formation of a two‐dimensional hydrogen‐bond network with sheets parallel to the (10) plane. Substituent effects on the crystal packing and coordination modes of the ligand are discussed. 相似文献