Lecture 6 ( MO Theory continued...) Flashcards
What does HOMO stand for?
Highest occupied molecular orbital
What does LUMO stand for?
Lowest unoccupied molecular orbital
What does LUMO stand for?
Lowest unoccupied molecular orbital
Why is HOMO and LUMO so important?
They are frontier orbitals and play a role in the chemistry of species
What is a ligand?
Anything that binds with a metal
Explain a back-donation.
when the ligand donates it electrons to the central atom, in which the central atom moves some of its electron density back into the ligand This create stability and maintenance of charge
What is isoelectronic mean?
molecules that bind to transition metals in the exact same fashion as certain molecules
Conditions for high LUMO
1) poor lewis acid
2) poor electrophile
3) difficult to reduce
Conditions for low LUMO
1) low in energy
2) good lewis acid
3) good electrophile
4) good oxidizing agent
5) electron acceptor
What is a symmetry operation?
an operation performed on an object that leaves its configuration indistinguishable and superimposable to the original
What is the Cn symmetry element mean?
Rotation about an n-fold axis of symmetry
What is the σ symmetry element mean?
reflection through a plane of symmetry (mirror plane)
what is the i symmetry element mean?
reflection through a centre of symmetry (inversion centre)
What is the Sn symmetry element mean?
rotation about an axis, followed by a reflection through a plane perpendicular to the axis (improper rotation axis)
What is the E symmetry element mean?
The identity operator, leaves the molecule unchanged
