A [Mn] Defective Supertetrahedron T3 and Its Dimeric [Mn] Analogue.

The initial use of 2-(pyridin-2-yl)propane-1,3-diol (pypdH) in Mn cluster chemistry has afforded two new mixed-valence polynuclear Mn clusters, namely, [MnΟ(pypd)(hmp)(OCCMe)] () and [MnΟ(N)(pypd){(py)CO}(OCEt)] () (hmp = deprotonated 2-hydroxymethylpyridine; (py)CO = deprotonated gem-diol form of di-2-pyridyl ketone). Compound features a novel [Mn Mn(μ-O)(μ-O)(μ-OR)] structural core resembling a supertetrahedron T3, lacking two apexes, while complex has a [Mn Mn (μ-O)(μ-O)(μ-N)(μ-OR)(μ-OR)] core consisting of two [Mn] subunits related to and thus is a dimeric analogue of . Direct current (dc) magnetic susceptibility studies revealed the presence of dominant antiferromagentic exchange interactions between the Mn ions in complexes and and small ground state spin values for both compounds.

Synthetic Factors Determining the Curvature and Nuclearity of the Giant Mn and Mn Clusters with a Torus Structure of ∼4 nm Diameter.

New members of the Mn and Mn torus-like cluster family have been prepared from a hybrid comproportionation-alcoholysis reaction of [MnO(OCR)(HO)] in alcohol in the presence of R'COH with NBuMnO or Mn salts as initiators. Reactions using MeCOH in PrOH or BuOH gave [MnO(OCMe)(OPr)(PrOH)(HO)] () and [MnO(OCMe)(OH)(OBu)(BuOH)(HO)] (), respectively, whereas EtCOH in PrOH gave [MnO(OCEt)(OPr)(PrOH)(HO)] (). They consist of alternating near-linear [Mn(μ-O)] and distorted-cubane [Mn(μ-O)(μ-OR)] units bridged by syn,syn-μ-RCO and μ-O groups and overall are [Mn] and [Mn] oligomers, the repeating unit containing two Mn and two Mn units.

Validation of the Green's Function Approximation for the Calculation of Magnetic Exchange Couplings.

In this work, we assess the potential of the Green's function approximation to predict isotropic magnetic exchange couplings and to reproduce the standard broken-symmetry energy difference approach for transition metal complexes. To this end, we have selected a variety of heterodinuclear, homodinuclear, and polynuclear systems containing 3d transition metal centers and computed the couplings using both the Green's function and energy difference methods. The Green's function approach is shown to have mixed results for the cases tested.

Magnetic Properties of High-Nuclearity Fe-oxo ( = 7, 22, 24) Clusters Analyzed by a Multipronged Experimental, Computational, and Magnetostructural Correlation Approach.

The synthesis, structure, and magnetic properties of three related iron(III)-oxo clusters are reported, [FeO(OCPh)(mda)(HO)] (), [FeO(OH)(OCMe)(mda)](ClO) (), and [FeO(OH)(OEt)(OCMe)(mda)](ClO) (), where mdaH is -methyldiethanolamine. was prepared from the reaction of [FeO(OCPh)(HO)](NO) with mdaH in a 1:2 ratio in MeCN, whereas and were prepared from the reaction of FeCl/NaOCMe/mdaH in a 2:∼13:2 ratio and FeCl/NaOCMe/mdaH/pyridine in a 2:∼13:2:25 ratio, respectively, both in EtOH. The core of consists of a central octahedral Fe ion held within a nonplanar Fe loop by three μ-O and three μ-RO arms from the three mda chelates.

Using Hyperoptimized Tensor Networks and First-Principles Electronic Structure to Simulate the Experimental Properties of the Giant {Mn} Torus.

The single-molecule magnet {Mn} is a challenge to theory because of its high nuclearity. We directly compute two experimentally accessible observables, the field-dependent magnetization up to 75 T and the temperature-dependent heat capacity, using parameter-free theory. In particular, we use first-principles calculations to derive short- and long-range exchange interactions and compute the exact partition function of the resulting classical Potts and Ising spin models for all 84 Mn = 2 spins to obtain observables.