Synthesis, Crystal Structure and Magnetic Properties of Three {(CrMnII)-Mn-III} Heterodimetallic Complexes Based on Heteroleptic Cyanido-Bearing Cr-III Building Blocks
Alexandru, MG; Visinescu, D; Braun-Cula, B; Lloret, F; Julve, M
| HERO ID | 4268258 |
|---|---|
| In Press | No |
| Year | 2018 |
| Title | Synthesis, Crystal Structure and Magnetic Properties of Three {(CrMnII)-Mn-III} Heterodimetallic Complexes Based on Heteroleptic Cyanido-Bearing Cr-III Building Blocks |
| Authors | Alexandru, MG; Visinescu, D; Braun-Cula, B; Lloret, F; Julve, M |
| Journal | European Journal of Inorganic Chemistry |
| Issue | 3-4 |
| Page Numbers | 349-359 |
| Abstract | The use of the heteroleptic [Cr-III(AA)(CN)(4)]-complexes as ligands towards the preformed [Mn-II(tptz)](2+) and [Mn-II(pyim)(2)](2+) species afforded the heterometallic compounds of formula [Mn-II(tptz)(H2O)(NO3)(mu-NC)Cr-III(ampy)(CN)(3)]center dot CH3CN (1), [Mn-II(tptz)(H2O)(NO3)(mu-NC) Cr-III(phen)(CN)(3)]center dot H2O (2) and {[Mn-II(pyim)(2)][(mu-NC) Cr(phen)(CN)(3)](2)}center dot 3H(2)O (3) [AA = 2-amino-methylpyridine (ampy) and 1,10-phenanthroline (phen), tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine and pyim = 2-(1H-imidazol-2yl) pyridine]. 1 and 2 are neutral heterodinuclear complexes, where the [Cr-III(AA)(CN) 4]-building block acts as a monodentate ligand through one of its four cyanido groups towards a manganese(II) ion with seven coordination sites completed by a tridenate tptz molecule, a bidentate nitrate anion and a water molecule. Compound 3 is a neutral heterotrinuclear complex made up by two peripheral [Cr-III(AA)(CN)(4)](-) units acting as monodentate ligands through one of their cyanido groups towards an inner [Mn-II(pyim)(2)](2+) entity. Each manganese(II) ion in 3 is six-coordinate with two cyanido nitrogen atoms and two bidentate pyim molecules, building a distorted octahedral surrounding. The values of the Cr-III-Mn-II distance across the bridging cyanido ligand are 5.3766(7) (1), 5.3194(6) (2) and 5.3245(8) and 5.4538(7) angstrom (3). The magnetic properties of 1-3 were investigated in the temperature range 1.9-300 K. Overall antiferromagnetic behaviour is observed for all three compounds, with the antiparallel alignment of the local spins leading to either a ground-state spin triplet (1 and 2) or a spin doublet (3). The values of the magnetic coupling between the Cr-III and Mn-II ions across the single cyanido bridges are J = -7.40(2) (1), -6.65(2) (2) and -6.41(2) and -4.65(2) cm(-1) (3), with the spin Hamiltonian being defined as H = -J(S-Cr1 center dot S-Mn1) (1 and 2) and H = -J(1)(S-Cr1 center dot S-Mn1) - J(2)(S-Cr2 center dot S-Mn2) (3). These values could be correlated with the Mn-N-Ccyanido angle, and they agree with those reported for this exchange pathway in other magnetostructural studies. |
| Doi | 10.1002/ejic.201700313 |
| Wosid | WOS:000423335900016 |
| Url | WOS:000428530600016 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Keyword | Chromium; Manganese; Heterometallic complexes; Structure elucidation; Magnetic properties |