Electronic, magnetic, and structural characterization of the five-coordinate, high-spin iron(II) nitrato complex [Fe(TpivPP)(NO3)]-.
The preparation and characterization of the five-coordinate iron(II) porphyrinate derivative [Fe(TpivPP)(NO3)]- (TpivPP = picket-fence porphyrin) is described. Structural and magnetic susceptibility data support a high-spin state (S = 2) assignment for this species. The anionic axial nitrate ligand is O-bound, through a single O atom, with an Fe-O bond length of 2.069(4) A. The planar nitrate ligand bisects a N(p)-Fe-N(p) angle. The average Fe-N(p) bond length is 2.070(16) A. The Fe atom is located 0.49 A out of the 24-atom mean porphyrin plane toward the nitrate ligand. From solid-state Mössbauer data, the isomer shift of 0.98 mm/s at 77 K is entirely consistent with high-spin iron(II). However the quadrupole splitting of 3.59 mm/s at 77 K is unusually high for iron(II), S = 2 systems but within the range of other five-coordinate high-spin ferrous complexes with a single anionic axial ligand. Crystal data for [K(222)][Fe(TpivPP)(NO3)] x C6H5Cl: a = 17.888 (5) A, b = 21.500 (10) A, c = 22.514 (11) A, beta = 100.32 (3) degrees, monoclinic, space group P2(1)/n, V = 8519 A3, Z = 4.
Nasri
Habib
H
Laboratoire de Physico-Chimie des Matériaux, Faculté des Sciences de Monastir, Avenue de l'environnement, 5019 Monastir, Tunisia.
Ellison
Mary K
MK
Shaevitz
Ben
B
Gupta
Govind P
GP
Scheidt
W Robert
WR
D007501:Iron / Q000737:chemistry*; D008280:Magnetics; D008665:Metalloporphyrins / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D009566:Nitrates / Q000138:chemical synthesis / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D015204:Spectroscopy, Mossbauer; D014961:X-Ray Diffraction
D008665:Metalloporphyrins; D009566:Nitrates; D009942:Organometallic Compounds; D007501:Iron