INORGANIC CHEMISTRY SUMMARY SHEET
Hume-Rothery rules for alloy solubility
1. The atomic radii of two kinds of atoms must
be similar (within ~15%) to reduce lattice
strain
2. The crystal structure of the two pure metals
must be identical
3. Similar valences and electronegativities are
required to minimize complexation
Splitting
Crystal field splitting (0) equals the energy of a
photon: 0 = 10 Dq = E = h
CFSE = (#e--)(eg= -3/5) + (#e--)(t2g =2/5)
What increases degree of d-orbital splitting
1. High oxidation number of metal center
2. Ligand from π-aceptor > σ-donor >π-donor
3. Unevenly filled degenerate orbitals
Ligand Field Theory
The transmitted light
is the complement of
the absorbed light.
Spin forbidden (b)
Because the electron
must “flip” its spin.
High spin/frequency
Low energy
Colorless
Paramagnetic
Low spin/frequency
High energy
Colored
diamagnetic
a) b)
Ligand Field Theory reactions
Small or zero LFSE: undergo substitution with t½ < 1 minute (liability)
Large LFSE: undergo substitution with t½ > 1 minute (inert)
Trans effect: CN- > P(C2H5)3 > NO2- ~ SCN- > Br- > Cl- > NH3 > H2O
Gibbs free energy
ΔG = ΔH – TΔS = -RT ln (K)
K[C][D]
[A][B]
ΔH = Bonds Broken
–
Bonds Formed
