### Degeneracy

Posted:

**Fri Jan 31, 2020 2:09 pm**I understand that degeneracy is the number of ways that a given energy state is achieved but what exactly is degeneracy used for?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=131&t=57786

Page **1** of **1**

Posted: **Fri Jan 31, 2020 2:09 pm**

I understand that degeneracy is the number of ways that a given energy state is achieved but what exactly is degeneracy used for?

Posted: **Fri Jan 31, 2020 2:28 pm**

Degeneracy can be used to describe systems when the systems are of different states, such as solid, liquid, or gas, but equal in energy levels.

Posted: **Fri Jan 31, 2020 3:57 pm**

Degeneracy is a way to quantify the possible number of positions a particular species can form. In relation to entropy, it can be seen as the number of Microstates/positions that are possible for a particular system.

Posted: **Fri Jan 31, 2020 4:10 pm**

asannajust_1J wrote:Degeneracy is a way to quantify the possible number of positions a particular species can form. In relation to entropy, it can be seen as the number of Microstates/positions that are possible for a particular system.

How do you determine the number of positions/microstates?

Posted: **Fri Jan 31, 2020 4:14 pm**

In class we determined the number of microstates by using the equation 2^N, where N is the number of atoms and 2 represents a 2-state system

Posted: **Fri Jan 31, 2020 4:25 pm**

Degeneracy is directly related to entropy and helps find positional entropy. With entropy solved, we can use delta H and entropy in an equation we'll learn later on to determine whether an equation is spontaneous or not.

Posted: **Fri Jan 31, 2020 4:59 pm**

We use the equation n^2. We use 2 because it's a two-state system and N represents the number of particles.

Posted: **Thu Feb 06, 2020 3:30 pm**

W, degeneracy is used in the equation S = kB*ln(W) to find the residual or positional entropy of a system

Posted: **Fri Feb 07, 2020 2:55 pm**

For this course, it can be used to calculate entropy via the Boltzmann equation, that is S = Kb * ln W, where W is the degeneracy. In general larger molecules will have greater degeneracy. However, this equation has a lot of error associated with it, as its relying on a whole number and a defined value to calculate the entropy value.

Posted: **Sat Feb 08, 2020 6:11 pm**

Isn't degeneracy used for the entropy equation (S=kBlnW)?