Molecular orbital/Talk

A really nice page. However a couple of things aren't transparent,

Molecular symmetries]? map [stationary states]? to stationary states, so any collection of degenerate? molecular orbitals must transform according to some representation? of the [symmetry group]?. As a result, basis orbitals that transform according to different representations don't mix.

Could you make this a little clearer please, I can't make head nor tail of it.

Also

On the other hand consider a hypothetical molecule of H3, with the atoms labelled H, H', H". Then we would expect three low energy combinations:

  1s + 1s" - 1s'           Symmetric
  1s - 1s"                 Antisymmetric
  1s + 1s' + 1s"           Symmetric

Is this correct ? The second combination has onlt 2 basis states and it's not blatenly obvious why the first is symmetric.

Theresa Knott