Reddit mentions of Modern Harmonic Technique: The Elements of Harmony (20890)

Glad to share music theory with someone who's interested. It's a great study!

There's a lot about intervals, harmonies, and counterpoint that can fix to particular emotions or atmospheres. But I don't think its still that simple ever and I have never come across a table or some reference that easily related different modes or keys to specific emotions. Music theory is itself largely about controlling and releasing tension and tension is built through dissonance which resolves into consonance. It's all kind of about how you weave tension and drama through a composition, both horizontally (counterpoint) and vertically (harmony).

If you'd like to learn more about theory there's lots of great resources. To study music properly though you really have to learn how to read it and doing a set of workbooks can be really valuable for becoming fluent. If you already read music and can read intervals off a staff you should be fine to take on harmony and counterpoint. Again, learning music theory is like learning math, you have to now the language first. I wrote a series of music lessons years ago on Bandamp, which you're welcome to read here. They don't cover a lot of depth though. If you want to really learn theory there are much better resources.

Books:

Any of the Mark Sanecki books are great. Especially the rudiments. They often contain lots of exercises which are really valuable. These are some books I learned from but honestly any one is probably great.

Rudiments: https://www.amazon.ca/Complete-Elementary-Music-Rudiments-2nd/dp/B00FBLQLMY

Harmony: https://www.amazon.com/Modern-Harmonic-Technique-Elements-Harmony/dp/9990597383

I don't know any good counterpoint books but I'm sure there's plenty. Counterpoint is all about writing melodies which are kind of the backbone to chord progressions. The harmony book covers it a little though.