Quintiles, Biquintiles and sesquiquadrate

What do these aspects do specifically?

these are quite minor aspects but appear as conjunctions in the harmonic charts. quintiles in the 5th harmonic and this is related to creative talent and such. I'm not sure about the sesquiquadrate, which harmonic it would be

Sesquiquadrate is a 135 degree aspect, so similar to semi-square. It is an 8th harmonic aspect, and it creates subtle tension between the planets involved.

I increasingly see quintiles (including biquintiles) as important. I think they indicate areas of talent plus ambition. For example, if someone has sun biquintile Pluto with one of the planets in the second house, s/he may focus on amassing a lot of wealth.

Sesqui-squares indicate tension, similar to the square and semi-square.