[Ipodlover]

Im using Spectoscopy by Pavia, lampman, Kriz and i'm going over reviewing, i noticed that i don't know why there is always the main ortho peak around 750, and there is always another 3 very small ones around 1700-1950, Same goes for para and meta subs.

What are these peaks? are they overtones?
Why is there 3 of them?

Also, i see in the main peak they label it as "meta subst. oop"

What does oop stand for?

Thanks.