# Sigma bond by combining two p orbitals

If I combine two p orbitals in such a way that they form σ bonds, which linear combination will represent bonding and antibonding?

My work on this problem:

\begin{align} &\text{Bonding:} &(\phi_1 - \phi_2)\\ &\text{Antibonding:} &(\phi_1 + \phi_2) \end{align}

where $$\phi_1$$ and $$\phi_2$$ are the wavefunctions of 1st and 2nd p orbitals.

Reason: While forming a bond, in bonding combination two lobes of same phase will overlap so they are actually mirror images of each other, and therefore they are negative of each other. While in antibonding combination opposite phase combine, so the wavefunctions are actually added. Is this correct?

• There is no point in tracking individual orbital signs, for they are all arbitrary anyway. Other than that, you are right. – Ivan Neretin Nov 8 '19 at 8:30
• Hi thanks for your reply! U are saying that what I have written ( Y1-Y2) for bonding and (Y1+Y2) for antibonding is correct? – Sasmit Vaidya Nov 8 '19 at 8:31
• Provided that both orbital signs are chosen in the same way with respect to the axis directed along the bond, yes. – Ivan Neretin Nov 8 '19 at 8:33
• I want to share a picture with you how can I do that – Sasmit Vaidya Nov 8 '19 at 8:34
• There is no need for a picture, I think you got it right. Then again, you may edit your question and attach the image to it. – Ivan Neretin Nov 8 '19 at 8:52