[jeffreyH (OP)]

I want to buy a text on quantum chemistry and since it won't be cheap I am looking for recommendations.

[chiralSPO]

A few questions to help refine the search:

Would you prefer:
1) A more qualitative, less math-heavy approach
2) Calculus/diff eq approach
3) matrix algebra
4) group theory

Are you interested in a more historical perspective or a workbook filled with problems etc?

Are you interested in computational chemistry (like density functional theory) or just the theoretical underpinnings of physical chemistry on a quantum level?

[jeffreyH (OP)]

Let me think about my answer and I'll get back to you.

[Bored chemist]

This one is widely used, if a little old.
https://global.oup.com/academic/product/molecular-quantum-mechanics-9780199541423?cc=gb&lang=en&

[jeffreyH (OP)]

This one is widely used, if a little old.
https://global.oup.com/academic/product/molecular-quantum-mechanics-9780199541423?cc=gb&lang=en&

That looks like a good text to get into the subject.

[jeffreyH (OP)]

A few questions to help refine the search:

Would you prefer:
1) A more qualitative, less math-heavy approach
2) Calculus/diff eq approach
3) matrix algebra
4) group theory

Are you interested in a more historical perspective or a workbook filled with problems etc?

Are you interested in computational chemistry (like density functional theory) or just the theoretical underpinnings of physical chemistry on a quantum level?

All of the above is of interest but for now a matrix algebra approach would fit in with what I am studying at the moment. For Christmas I am getting a scientific biography of Wolfgang Pauli. I will read that first.

[chiralSPO]

Here is another free resource, which is an introduction to quantum mechanics of physical chemistry:
https://ocw.mit.edu/courses/chemistry/5-61-physical-chemistry-fall-2007/lecture-notes/

The textbook I used as an undergrad in physical chemistry (comprehensive across quantum and thermo) is:
https://www.amazon.com/Physical-Chemistry-Molecular-Donald-McQuarrie/dp/8176490016/ref=mt_paperback?_encoding=UTF8&me=
You can get the paperback new for under $40, but it is a big enough book that the sturdier hardcover will survive longer, but I think is around $100–$120

If you already have the basics, and are interested in how molecular matter interacts with the EM spectrum (specifically UV–IR), "Symmetry and Spectroscopy" is an excellent textbook (and only $15, used, or $32 new!) for using group theory and matrix algebra to understand the dynamics of small molecules (electronic and vibrational states)
https://www.amazon.com/Symmetry-Spectroscopy-Introduction-Vibrational-Electronic/dp/B01K2P8B2Q

[zmth]

What are u talking expensive ? A very good one is free by Schiff. Just google
 ' schiff quantum mechanics pdf free download ' 
and you will get it. Besides that just check out from a library by Vladimar Rojansky
' Introductory Quantum Mechanics '
or u can buy it if u insist.

Do not try to bypass anything or use any modern supposedly simplifying or whatever ...because all u will learn is the WRONG, misleading thing(s). You must stick with the traditional and some basic math such as eigenfunctions and eigenvalues, and be able to work with partial differential equation operators which is simply knowing how to differentiate , multiply matrices - the basics nothing really advanced to start off non-relativistic quantum theory.