10.1021/ja051233z.s005 Rasmus D. Poulsen Rasmus D. Poulsen Anders Bentien Anders Bentien Marie Chevalier Marie Chevalier Bo B. Iversen Bo B. Iversen Synthesis, Physical Properties, Multitemperature Crystal Structure, and 20 K Synchrotron X-ray Charge Density of a Magnetic Metal Organic Framework Structure, Mn<sub>3</sub>(C<sub>8</sub>O<sub>4</sub>H<sub>4</sub>)<sub>3</sub>(C<sub>5</sub>H<sub>11</sub>ON)<sub>2</sub> American Chemical Society 2005 Bader topological analysis electron Magnetic Metal Organic Framework Structure C 5 H 11 6.0 μ B Mn 3 Orbital population analysis phase transition C 8 O 4 H 4 topological measures show 20 K data Multitemperature Crystal Structure Magnetic susceptibility measurements 2005-06-29 00:00:00 Dataset https://acs.figshare.com/articles/dataset/Synthesis_Physical_Properties_Multitemperature_Crystal_Structure_and_20_K_Synchrotron_X_ray_Charge_Density_of_a_Magnetic_Metal_Organic_Framework_Structure_Mn_sub_3_sub_C_sub_8_sub_O_sub_4_sub_H_sub_4_sub_sub_3_sub_C_sub_5_sub_H_sub_11_sub_ON_sub_2_sub_/3279904 A new magnetic metal organic framework material has been synthesized, Mn<sub>3</sub>(C<sub>8</sub>O<sub>4</sub>H<sub>4</sub>)<sub>3</sub>(C<sub>5</sub>H<sub>11</sub>ON)<sub>2</sub>, <b>1</b>. Magnetic susceptibility measurements from 2 to 400 K reveal anti-ferromagnetic ordering at ∼4 K and a total magnetic moment of 6.0 μ<sub>B</sub>. The magnetic phase transition is confirmed by heat capacity data (2−300 K). The crystal structure is studied by conventional single-crystal X-ray diffraction data at 300, 275, 250, 225, 200, 175, 150, 125, and 100 K, and synchrotron data at 20 K. There is a phase transition between 100 and 20 K due to ordering of the diethylformamide molecules. The X-ray charge density is determined based on multipole modeling of a second 20 K single-crystal synchrotron radiation data set. The electron distributions around the two unique Mn centers are different, and both have substantial anisotropy. Orbital population analysis reveals large electron donation (1.7 e) to each Mn atom and the maximum possible number of unpaired electrons is 3.2 for both Mn sites. Thus, there is a considerable orbital component to the magnetic moment. Bader topological analysis shows an absence of Mn−Mn bonding, and the magnetic ordering is via super-exchange through the oxygen bridges. Formal electron counting suggests Mn<sup>2+</sup> sites, but this is not supported by the Bader atomic charges, Mn(1) = +0.11e, Mn(2) = +0.17e. The topological measures show the dominant metal−ligand interactions to be electrostatic, and a simple exponential correlation is derived between Mn−O bond lengths and the values of ∇<sup>2</sup>ρ at the bond critical points.