Charge-density study of deuterated ammonium ferrous Tutton salt at 85 K and comparison with Cr^II and Cu^II salts

Bond Characterization of Metal Squarate Complexes [MII(C4O4)(H2O)4; M = Fe, Co, Ni, Zn]

“…The difference in the charges of squarate is the reflection of Zn being much more positive than the other metal ions, which has the same trend in the Tutton salt for Cu (+1.8) versus the other metal ions (+0.7 to +1.2). 5 The coordinated H 2 O molecule is slightly positive, which is similar to the case of the Tutton salts. Overall, one can probably say that electron transfer is from H 2 O to the metal center, and then from the metal ion to the squarate dianion.…”

“…The electron density distribution of transition metal complexes has been investigated extensively using the single-crystal X-ray diffraction method during the last decade. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] Systematic studies on the 3d-transition metal complexes are made for the purpose of understanding the trend of electronic structure around the metal ion. The electronic structures of hexaaquametal(II) ions [1][2][3][4][5][6][7][8][9][10][11][12][13] are of archetypal importance in understanding metalligand (oxygen) bonds.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] Systematic studies on the 3d-transition metal complexes are made for the purpose of understanding the trend of electronic structure around the metal ion. The electronic structures of hexaaquametal(II) ions [1][2][3][4][5][6][7][8][9][10][11][12][13] are of archetypal importance in understanding metalligand (oxygen) bonds. Ammonium metal Tutton salts, (NH 4 ) 2 -[M II (H 2 O) 6 ](SO 4 ) 2 (M II ) V, 15,20 Cr, 3 Mn, 14,21 Fe, 5,16,20 Co, 20 Ni, 1,22 Cu, 2,4,23,24 Zn 25 ), have been studied by X-ray [1][2]…”

“…The electronic structures of hexaaquametal(II) ions [1][2][3][4][5][6][7][8][9][10][11][12][13] are of archetypal importance in understanding metalligand (oxygen) bonds. Ammonium metal Tutton salts, (NH 4 ) 2 -[M II (H 2 O) 6 ](SO 4 ) 2 (M II ) V, 15,20 Cr, 3 Mn, 14,21 Fe, 5,16,20 Co, 20 Ni, 1,22 Cu, 2,4,23,24 Zn 25 ), have been studied by X-ray [1][2][3][4][5][6] and polarized neutron diffraction, [11][12][13] where detailed charge [1][2][3][4][5][6] and spin densities [11][12][13] are given. The extent of σ and π metalwater bonding, electron correlation effects, and spin-orbit coupling effects are also discussed.…”

“…The extent of σ and π metalwater bonding, electron correlation effects, and spin-orbit coupling effects are also discussed. [1][2][3][4][5][6][11][12][13] The Jahn-Teller distortions are demonstrated in Cr(II) 3 and Cu(II) 2,4 complexes in comparison with the nondistorted Fe(II) 5 complex. These series of studies give a good example that by systematically varying the central 3d-transition metal in an isostructural environment, detailed information can be provided not only on the metal ligand bond but also on the crystal field effect exerted on the metal ions.…”