topic 4 Flashcards
what changes across a node
the sign of the wave function
which d orbitals lie between the cartesian axis
dxy
dzy
dzx
which d orbitals lie on the cartesian axis
dz^2
d x2 - y2
what does orbital energy depend on
depends on the e- inside of them
what is the orbital energy when there are no e- inside them
0 orbital energy when the orbital is empty
where are d orbitals degenerate
they’re degenerate in:
a vacuum
a spherical field of negative charge
what is the difference between d orbitals in a vacuum and in a spherical field of negative charge
in the spherical field, the orbitals have higher energy but are still degenerate
what is the crystal field theory
an ionic model that considers metals and ligands as point charges
what are the point charges of the metal and ligand
M = +
L = -
what holds the metal ligand complex
the electrostatic forces of attraction between the M+ and L-
what interaction does CFT focus on
how the interaction of the ligand and metal affects the d orbital energy
what can CFT explain
spec
magnetism
reactivity trends in d block compounds
when an octahedral complex is affected by a crystal field, what happens
5 splits into
2 eg (higher energy - directed towards ligands)
3 t2g (lower energy - lie between ligands and the cartesian axis )
what is the crystal field splitting energy for octahedral complex’s
🔺o
separation between eg and t2g
what factors affect magnitude of 🔺o
- nature of metal
- metal charge
- metal group position
- ligand
how does the metal charge effect 🔺o
higher + charge = higher oxidation state
= smaller metal ion
= shorter ML bond distance
= stronger interaction energy
= larger 🔺o
how does the metals group position affect 🔺o
🔺o increases by 20%-50% for each successive TM row
larger size = larger overlap with ligand
what ligands cause a larger 🔺o
halides = slow separation
CN- , CO= strong binding = toxic = larger 🔺o
what TM make a tetrahedral shape
mostly first row TM
how do tetrahedral complex’s split in a crystal field
3 = t2 = higher energy (closer alignment to ligands)
2 = e = lower energy ( low alignment to ligands)
what is different to the splitting in tetrahedral and octahedral complexes
in tetrahedral complexes, no orbital align exactly to the ligand
what is the crystal field splitting energy gap in tetrahedral complex’s
🔺t
what is eg
high energy
octahedral
doubly degenerate 2
what is e
lower energy
tetrahedral
doubly degenerate 2
what is t2
high energy
tetrahedral
triply degenerate
what is t2g
low energy
octahedral
triply degenerate
