7773-01-5Relevant articles and documents
Chlorination of manganese oxides
Fouga, Gastón G.,De Micco, Georgina,Bohé, Ana E.
, p. 141 - 146 (2009)
In this work the reaction between several manganese oxides and chlorine is investigated. The reaction path for the chlorination of the oxides is established, which involves recrystallization of high valence manganese oxides: Mn3O4 an
MASS-SPECTROMETRIC MEASUREMENTS OF THERMODYNAMIC PROPERTIES OF THE MOLTEN KCl-MnCl2 SYSTEM.
Sasamoto,Itoh,Sata
, p. 2415 - 2419 (1983)
Activities and heats of mixing for the molten KCl-MnCl//2 system were determined mass-spectrometrically by the ion-current ratio method. Activities of components KCl and MnCl//2 show large negative deviations from Raoult's law, indicating a very strong interaction between KCl and MnCl//2. Entropies of mixing calculated from measured activities and heats of mixing have minimum values in the vicinity of 33% MnCl//2, and have been compared with those calculated on the basis of some molten structure models to infer possible chemical species in the molten salt.
Formation of super disperse phase and its influence on equilibrium and thermodynamics of thermal dehydration
Polyachenok,Dudkina,Branovitskaya,Polyachenok
, p. 44 - 53 (2008)
New data on the dehydration and rehydration processes of calcium, manganese and copper dichlorides are presented that reveal surprising, in a certain sense, behaviour difficult to be explained for the last two chlorides in terms of the usual conception of thermodynamic equilibrium. A substantial role of a super disperse phase at studying the equilibrium of the thermal decomposition of a hydrate is postulated to explain the experimental results for manganese and copper dichlorides. It is shown that the formation of such a phase of the hydrate is able to change appreciably the experimental results, causing the increase of water vapour pressure and the decrease of the derived enthalpy of a reaction. The results obtained allow to understand the reasons for considerable differences of some literature data. They enable to receive more precise and reliable data for thermal dehydration and probably for some other decomposition processes.
Study on coordination behaviour of manganese chloride with L-α-histidine
Shengli,Sanping,Huanyong,Rongzu,Qizhen
, p. 795 - 805 (2004)
The reaction thermodynamic and kinetic equations for the non-reversible reactions are established. The enthalpy change of formation reaction of manganese(II) histidine (His) complex in water has been determined by microcalorimetry, using manganese chlorid
Coordination chemistry in the solid state: Reactivity of manganese and cadmium chlorides with imidazole and pyrazole and their hydrochlorides
Adams, Christopher J.,Kurawa, Mukhtar A.,Orpen, A. Guy
, p. 10475 - 10485 (2010)
Crystalline coordination compounds [MnCl2(Hpz)2] 3, [CdCl2(Hpz)2] 5, [MnCl2(Him)2] 9, and [CdCl2(Him)2] 13 (Him = imidazole; Hpz = pyrazole) can be synthesized in solid state reactions by grinding together the appropriate metal chloride and 2 equiv of the neutral ligand. Similarly, grinding together the metal chlorides with the ligand hydrochloride salts produces the halometallate salts [H2pz][MnCl3(OH2)] 1, [H2pz][CdCl4] 4, [H2im]6[MnCl 6][MnCl4] 8, and [H2im]6[CdCl 6][CdCl4] 11. In contrast, reacting the metal chloride salt with the ligand in concentrated HCl solution yields a second set of salts [H2pz][MnCl3] 2, [H2im][MnCl 3(OH2)2] 7, and [H2im][CdCl 3(OH2)]·H2O 12. Compound 5 can be partly dehydrochlorinated by grinding with KOH to form an impure sample of the pyrazolate compound [Cd(pz)2] 6, while recrystallizing 9 from ethanol yielded crystals of solvated [Mn4Cl8(Him)8] 10. The crystal structure determinations of 1, 2, 4, 11, and 12 are reported.
Pyridine-type complexes of transition-metal halides. Part XV. Mn(II) chloride complexes with 3,4- and 3,5-lutidine
Szecsenyi, K. Mészáros,Wadsten,Kovács,Liptay
, p. 965 - 974 (2004)
Manganese(II) chloride complexes with 3,4- and 3,5-lutidine have been prepared. The crystal symmetry and cell dimensions have been calculated on the basis of powder diffraction data. The compounds were characterised also by FT-IR spectrometry. The thermal
Evolution from discrete mononuclear complexes to trinuclear linear cluster and 2D coordination polymers of Mn(II) with dihydrazone Schiff bases: Preparation, structure and thermal behavior
Bourosh, Paulina N.,Bulhac, Ion,Ch. Kravtsov, Victor,Cocu, Maria,Croitor, Lilia,Danilescu, Olga,Petuhov, Oleg
, (2021)
Four Mn(II) coordination compounds based on the 2,6-diacetylpyridine bis(isonicotinoylhydrazone) (H2L1) and 2,6-diacetylpyridine bis(nicotinoylhydrazone) (H2L2), were prepared using different synthetic condition
Microcalorimetry study of the reactivity of two manganese ammonia chlorides
Marty A.
, p. 479 - 498 (1991)
The reaction [Mn(NH3)2]Cl2 + 4NH3 [Mn(NH3)6]Cl2, which is of potential use in chemical heat pumps, was studied by means of differential scanning calorimetry. The thermodynamic c
Enhanced Stability of the FeII/MnII State in a Synthetic Model of Heterobimetallic Cofactor Assembly
Kerber, William D.,Goheen, Joshua T.,Perez, Kaitlyn A.,Siegler, Maxime A.
, p. 848 - 857 (2016)
Heterobimetallic Mn/Fe cofactors are found in the R2 subunit of class Ic ribonucleotide reductases (R2c) and R2-like ligand binding oxidases (R2lox). Selective cofactor assembly is due at least in part to the thermodynamics of MII binding to the apoprotein. We report here equilibrium studies of FeII/MnII discrimination in the biomimetic model system H5(F-HXTA) (5-fluoro-2-hydroxy-1,3-xylene-α,α′-diamine-N,N,N′,N′-tetraacetic acid). The homobimetallic F-HXTA complexes [Fe(H2O)6][1]2·14H2O and [Mn(H2O)6][2]2·14H2O (1 = [FeII2(F-HXTA)(H2O)4]-; 2 = [MnII2(F-HXTA)(H2O)4]-) were characterized by single crystal X-ray diffraction. NMR data show that 1 retains its structure in solution (2 is NMR silent). Metal exchange is facile, and the heterobimetallic complex [FeIIMnII(F-HXTA)(H2O)4]- (3) is formed from mixtures of 1 and 2. 19F NMR was used to quantify 1 and 3 in the presence of excess MII(aq) at various metal ratios, and equilibrium constants for FeII/MnII discrimination were calculated from these data. FeII is preferred over MnII with K1 = 182 ± 13 for complete replacement (2 21). This relatively modest preference is attributed to a hard-soft acid-base mismatch between the divalent cations and the polycarboxylate ligand. The stepwise constants for replacement are K2 = 20.1 ± 1.3 (2 23) and K3 = 9.1 ± 1.1 (3 21). K2 > K3 demonstrates enhanced stability of the heterobimetallic state beyond what is expected for simple MnII FeII replacement. The relevance to FeII/MnII discrimination in R2c and R2lox proteins is discussed.
Infrared spectra of CX3-MnX and CX2=MnX2 (X = H, F, Cl) prepared in reactions of laser-ablated manganese atoms with halomethanes
Cho, Han-Gook,Andrews, Lester
, p. 477 - 486 (2011)
Small manganese insertion (CX3-MnX) and methylidene (CX 2=MnX2) complexes, carrying the highest multiplicities (sextet and quartet) among the analogous group 3-12 metal complexes, are produced in laser-ablated Mn atom reactions with halomethanes and identified in matrix infrared spectra with isotopic shifts and DFT frequency calculations. The linear C-M-X structure of the Mn insertion complexes resembles that of Grignard reagent molecules unlike those of other transition-metal analogues except Fe, and the Mn-C bond bears high s character, on the basis of DFT calculations. The Mn methylidenes have planar structures, common among early transition-metal analogues, revealing that Mn has borderline properties between the early and late transition metals. The computed C-Mn bond lengths of the carbene complexes in the quartet states (1.855-1.872 A) are considerably shorter than those of the insertion complexes in the sextet states (2.057-2.120 A), which is likely due to the one-half π-bond order and large ionic contribution to bonding in the carbene complexes. The tendency of increasing preference for higher oxidation-state products on going down in a family group is most dramatic among the group 7 metals Mn and Re.
