What's written below is a preliminary sketch of what we find in the SCG regarding God's emotions or lack thereof. I've long been interested in this subject because it seems to me that whether God is moved by our human plight or not, makes a difference theologically and existentially. I hope to develop these basic ideas as time goes on. If not, maybe posterity will finish my work. :)
Summa Contra Gentiles I.LXXXIX.12
Differentiating emotions and passions
"No passion in intellective appetite" (Aquinas)
God does not acquire knowledge through the senses and thus has no sensitive appetite (could this be reversed?), there could be no need for sensitive appetite
Every passion is accompanied by somatic change (alteration) but God is not a body (ST I.3.1, maybe)
Emotions (passions) draw one outside the connatural disposition. But God cannot be withdrawn from outside of the connat. disposition since God is utterly immutable.
Passion has one object
Every passion is also in a subject "that is in potentiality." Yet God has no potential whatsoever.
Sorrow or pain [evils inherently by species] cannot be in God.
Repentance "denotes a change in the appetite." Repentance is a kind of sorrow: it thus implies a change of will.
God cannot be angry:
See SCG I.91.16-18 and II.2.5.9