TY - JOUR

T1 - Behavior of MnIV in the hexaniobate, telluropentaniobate and hexatantalate solutions

AU - Abramov, Pavel A.

AU - Akhmetova, Maria M.

AU - Romanova, Tamara E.

AU - Bogomyakov, Artem S.

AU - Fedin, Matvey V.

AU - Sokolov, Maxim N.

PY - 2018/3/24

Y1 - 2018/3/24

N2 - Reactions of K7H[Nb6O19], K6[(OH)TeNb5O18] or Na8[Ta6O19] with Mn(OAc)2 in the presence of H2O2 lead to the formation of brown solutions. In the case of the hexaniobate crystallization gives orange crystals of K9Na2[HMn(Nb6O19)2]·18·5H2O (1), characterized by XRD, XRPD and EPR. Magnetic properties and stability of 1 in aqueous solution have been studied. The rate of formation of the telluropentaniobate analogue, [Mn(TeNb5O19)2]10−, is much more slow. It is relatively stable in solution, though less so than the hexaniobate complex, and could not be isolated. In the case of hexatantalate the reaction solution is unstable and transforms into an intractable brownish amorphous precipitate. EPR studies of the solids isolated from the reactions with [(OH)TeNb5O18]6− and [Ta6O19]8− suggest oligomeric or polymeric nature of the solids, with the formation of {MnIV xOy} aggregates.

AB - Reactions of K7H[Nb6O19], K6[(OH)TeNb5O18] or Na8[Ta6O19] with Mn(OAc)2 in the presence of H2O2 lead to the formation of brown solutions. In the case of the hexaniobate crystallization gives orange crystals of K9Na2[HMn(Nb6O19)2]·18·5H2O (1), characterized by XRD, XRPD and EPR. Magnetic properties and stability of 1 in aqueous solution have been studied. The rate of formation of the telluropentaniobate analogue, [Mn(TeNb5O19)2]10−, is much more slow. It is relatively stable in solution, though less so than the hexaniobate complex, and could not be isolated. In the case of hexatantalate the reaction solution is unstable and transforms into an intractable brownish amorphous precipitate. EPR studies of the solids isolated from the reactions with [(OH)TeNb5O18]6− and [Ta6O19]8− suggest oligomeric or polymeric nature of the solids, with the formation of {MnIV xOy} aggregates.

KW - CRYSTAL-STRUCTURE

KW - ANION

KW - POLYOXONIOBATES

KW - MANGANESE(4)

KW - NIOBATES

UR - http://www.scopus.com/inward/record.url?scp=85041586568&partnerID=8YFLogxK

U2 - 10.1016/j.ica.2018.01.012

DO - 10.1016/j.ica.2018.01.012

M3 - Article

AN - SCOPUS:85041586568

VL - 473

SP - 268

EP - 274

JO - Inorganica Chimica Acta

JF - Inorganica Chimica Acta

SN - 0020-1693

ER -