splitting a site collection into 2 new site collections - one of which is in another content database

I am hoping someone might be aware of some powershell that would help me with this functionality.

I have a site collection that currently holds 2 departments. The name of both departments is in the name of the site collection.

We are moving to a model where each department is in a separate site collection, and each division has its own content database.

So, I need to:

a. create 2 new site collections, each containing the appropriate parts of the original.

b. move one of the new site collections to its own content database.

Are there any articles, tutorials, etc. that cover doing this type of thing within PowerShell?

Thank you!