[mana]

hi all
when we talk about atomic orbital overlap, we assume them as wave function and divide this overlap as
 1-constructive (in-phase)
 2- destructive (out of phase)
my question is, how I can determine which atom orbitals will overlap constructively or destructively?
does the orientation of spin affect overlap qualification? for one thing can I say the two atomic orbitals with the same electron spin orientations will overlap destructively and reverse?
thanks in advance for your help

[Orcio_87]

does the orientation of spin affect overlap qualification? for one thing can I say the two atomic orbitals with the same electron spin orientations will overlap destructively and reverse?

No. The overlap is constructive when signs of the wave-function are the same or destructive when signs of the wave are opposite.

[Orcio_87]

I meant - signs of the wave-functionS.

[mana]

thanks for your answer. 
if two atomic orbitals with the same electron spin, overlap constructively with each other, what would happen? I mean one of the electrons has to change its spin? because as you know in a molecular orbital the electron spins must be opposite, or something else would happen?

[Orcio_87]

One of the electron will change its spin.