Of the two possible geometrical isomers (i.e., facial and meridional), the cation takes the meridional form with the three coordinated imine nitrogen atoms or the three coordinated imidazole nitrogen atoms in the meridional positions. By analyzing the Fe–N bond distances and N–Fe–N bond angles, the spin state can be identified.Cited by: 11. Dear student! Facial and meridional isomers are found in octahedral complexes of MA 3 B 3 type.. Facial Isomer (fac-isomer): It is the cis isomer form of the complex in which the similar groups of ligands are at the corners of one of the octahedral faces.3.8/5(4).
2 mer-counterparts.17 This is so because larger nonradiative decay rates are generally obtained for the latter isomers, whilst the radiative rates remain alike for both isomers. Additionally, the mer-isomer is usually more susceptible to degradation than the fac-isomer upon PhOLED operation.18 These features hold generally true for all kind of cyclometalating ligands (e.g.,Cited by: 4. Mar 31, 2016 · Facial and meridional isomers are possible with respect to the octahedral complex. The Co(III) has two geometric isomers available: facial, 3 ligands occupy the face of an octahedron; meridional, where 2 of the ligands are trans, and the third is cis.
The meridional and facial isomers of triamminechromium pyrophosphate were separated by chromatography on Dowex-50-H+, and crystallized as isoionic species. When three ligands are found in a row on an octahedron, the geometry is called "meridional" or simply "mer". When the three cluster together in a triangle, the geometric relationship is called "facial" or simply "fac". Figure SC17.2. The fac- and mer- configurations of (NH 3) 3 CoCl 3. Go to Animation SC17.3.