High-spin and Low-spin Systems
The first d electron count (special version of electron configuration) with the possibility of holding a high spin or low spin state is octahedral d4 since it has more than the 3 electrons to fill the non bonding d orbitals according to ligand field theory or the stabilized d orbitals according to crystal field splitting. The spin state of the complex also affects an atom's ionic radius.
- d4
- Octahedral high-spin: 4 unpaired electrons, paramagnetic, substitutionally labile. Includes Cr2+ ionic radius 80 pm, Mn3+ ionic radius 64.5 pm.
- Octahedral low-spin: 2 unpaired electrons, paramagnetic, substitutionally inert. Includes Cr2+ ionic radius 73 pm, Mn3+ ionic radius 58 pm.
- d5
- Octahedral high-spin: 5 unpaired electrons, paramagnetic, substitutionally labile. Includes Fe3+ ionic radius 64.5 pm.
- Octahedral low-spin: 1 unpaired electron, paramagnetic, substitutionally inert. Includes Fe3+ ionic radius 55 pm.
- d6
- Octahedral high-spin: 4 unpaired electrons, paramagnetic, substitutionally labile. Includes Fe2+ ionic radius 78 pm, Co3+ ionic radius 61 pm.
- Octahedral low-spin: no unpaired electrons, diamagnetic, substitutionally inert. Includes Fe2+ ionic radius 62 pm, Co3+ ionic radius 54.5 pm, Ni4+ ionic radius 48 pm.
- d7
- Octahedral high-spin: 3 unpaired electrons, paramagnetic, substitutionally labile. Includes Co2+ ionic radius 74.5 pm, Ni3+ ionic radius 60 pm.
- Octahedral low-spin:1 unpaired electron, paramagnetic, substitutionally labile. Includes Co2+ ionic radius 65 pm, Ni3+ ionic radius 56 pm.
- d8
- Octahedral high-spin: 2 unpaired electrons, paramagnetic, substitutionally labile. Includes Ni2+ ionic radius 69 pm.
- Square planar low-spin: no unpaired electrons, diamagnetic, substitutionally inert. Includes Ni2+ ionic radius 49 pm.
Read more about this topic: Spin States (d Electrons)
Famous quotes containing the word systems:
“What is most original in a man’s nature is often that which is most desperate. Thus new systems are forced on the world by men who simply cannot bear the pain of living with what is. Creators care nothing for their systems except that they be unique. If Hitler had been born in Nazi Germany he wouldn’t have been content to enjoy the atmosphere.”
—Leonard Cohen (b. 1934)