# What are two molecular states ?

1. Oct 26, 2009

### xylai

In molecular orbital theory, there are two molecular states. (see below)

I don't know the differences between these two states?

#### Attached Files:

• ###### 未命名.JPG
File size:
5 KB
Views:
240
2. Oct 27, 2009

### alxm

The difference is one of them has an apostrophe.

Seriously though, to my knowledge there's no system of notation for atomic or molecular orbitals which uses the prime symbol for anything in particular. I'm guessing in the context they're denoting a particular atom's 1s orbital with a prime and another's without.

Writing $$\sigma_g1s$$ doesn't quite make sense by itself either - sigma is an MO, 1s is an atomic orbital, and you need at least two of those to get an MO.

$$\sigma_g$$ signifies the even (gerade) symmetry, it's the same as the bonding sigma orbital.