All Questions
Tagged with symmetry quantum-chemistry
25
questions
3
votes
1
answer
137
views
Spatial Wavefunction Symmetries and Identical Particles
I was reading this and it mentions in the 3-electron section, that for a spacial wave function to be symmetric under fermion swapping, it must be a function of even parity. Similarly for anti-symmetry ...
- 133
4
votes
0
answers
62
views
Multiplicity letter codes for large amount of states
Well, let's say we have a large amount of states computed (e.g. over 50), all with the same multiplicity.
So, our ground state can be $X^2\Sigma^+_g$ and we can continue with $B^2, C^2$ etc. as ...
- 1,267
13
votes
2
answers
2k
views
Relationship between the symmetry number of a molecule as used in rotational spectroscopy and point group
While doing a problem set I noticed that the symmetry number of a molecule turns out (usually) to be half the number of symmetry elements that the point group the molecule belongs to.
When I say ...
- 1,443
5
votes
0
answers
226
views
How to derive a state symmetry in D2h point group from its wavefunction?
Let's have an atomic carbon with the following electron configuration:
$$
1s^2 2s^2 2p^2
$$
One of it's levels is ${}^1S_0$, which is corresponding with the following state:
$$
\begin{align}
\left| ...
- 1,267
4
votes
1
answer
349
views
Molecular orbitals symmetry - states notation
I'm reading some papers and I'm repeatedly seeing the following notation of system states:
Could you, please, explain to me the meaning of it?
E.g. the state $B^2 \Sigma_u^+$ - I'm aware, that $\...
- 1,267
4
votes
1
answer
217
views
Breaking degeneracy in phosphorus pentachloride
Recently, in a class discussion, the following point was brought up:
Although the axial and equatorial bond lengths in $\ce {PCl5}$ are inequivalent, when we consider the time-averaged $\ce {P-Cl}$...
- 10.7k
15
votes
2
answers
463
views
What constraints are imposed on a wavefunction by the symmetry of the system?
As a follow-up to my answer here, I'd like to ask what exactly does it mean for a wavefunction to "respect the symmetry" of the system.
The original context is: immediately after ionisation of $\ce{...
- 71.6k
8
votes
1
answer
3k
views
Determination of +/- reflections in sigma molecular term symbols
This page, which depicts the molecular term symbols for the $\ce{O2}$ and $\ce{O2-}$ (Edit: Mistaken on $\ce{O2-}$) molecules, perhaps best summarizes the full scope of my questions. In general, I don'...
- 1,648
5
votes
1
answer
914
views
Is there an example of a closed shell molecule with a permanent ground state magnetic dipole?
It seems that molecules of point group C$_{n}$ and C$_{nh}$ can in principle support a permanent magnetic dipole moment (Barron, 2004). However, I cannot think of any closed shell molecules that ...
- 2,120
21
votes
2
answers
6k
views
Jahn-Teller Distortions in Square Planar Complexes?
A Jahn-Teller distortion is predicted whenever a non-linear symmetric molecule has degenerate orbitals and has unequal electron occupation in those degenerate orbitals. Of course, this most often is ...
- 27.9k