## Atomic Spectroscopy v. Molecular Spectroscopy

H-Atom ($E_{n}=-\frac{hR}{n^{2}}$)

Neel Bonthala 2G
Posts: 98
Joined: Wed Sep 30, 2020 9:40 pm

### Atomic Spectroscopy v. Molecular Spectroscopy

Going through the learning objectives in the Quantum World outline, I found the following objective:

"With respect to electron transitions that give rise to a UV or visible spectrum: understand the difference between electronic transitions in atomic orbitals (atomic spectroscopy) and electronic transitions in molecular orbitals (molecular spectroscopy)."

I understand that both atomic and molecular spectroscopy share many similarities in regards to how electrons absorb energy when excited and subsequently emit photons as they fall back, creating spectra. But what exactly are the differences between electronic transitions?

Ayesha Aslam-Mir 3C
Posts: 118
Joined: Wed Sep 30, 2020 9:43 pm

### Re: Atomic Spectroscopy v. Molecular Spectroscopy

Hi Neel,

I'm just going to assume the energy differences are vastly different (for lack of a better term) due to the electrongeativity of an atom of an element as opposed to the attraction (pull) of either a stable or unstable compound. I do not recall seeing any probelms requiring an ability to differentiate these levels in any of the lecture content thus far, but if anyone could provide an update on this, that would be great! (I will if I come across any!)

Thomas Vu 1A
Posts: 113
Joined: Wed Sep 30, 2020 10:08 pm
Been upvoted: 1 time

### Re: Atomic Spectroscopy v. Molecular Spectroscopy

Since this class is an introductory course to chemistry, I think we won't learn this material until later on but at this stage, questions have only been focused on the electron transitions of a Hydrogen atom spectrum. For that, we have the En and Rydberg equation.

Astha Sahoo 3I
Posts: 100
Joined: Wed Sep 30, 2020 9:52 pm
Been upvoted: 1 time

### Re: Atomic Spectroscopy v. Molecular Spectroscopy

In one of the UA sessions I think someone said that electronic transitions in molecules are more complicated and complex than electronic transitions in atoms, because there's more subshells. We haven't gone into a lot of depth on the topic though so I'm assuming we won't be tested on it on this first midterm.