## 2F.2 Conceptual Textbook Question

(Polar molecules, Non-polar molecules, etc.)

Sofia Lucido 3L
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### 2F.2 Conceptual Textbook Question

Hi everyone,

At the bottom of page 119 of the textbook (in section 2F.2) it showed how each hybrid orbital is a linear combination of the four atomic orbitals:
$h_{1}=s+p_{x}+p_{y}+p_{z}$
$h_{2}=s-p_{x}-p_{y}+p_{z}$
$h_{3}=s-p_{x}+p_{y}-p_{z}$
$h_{4}=s+p_{x}-p_{y}-p_{z}$

It says in h1 the s and p orbitals all have their usual signs, and their amplitudes add together where they are all positive. In h2 however the signs of px and py are reversed, and so the resulting interference pattern is different.

I can remember back to when we talked about wave interference, but I am a little bit confused about what the negative and positive signs mean in front of the s and p orbitals. Can someone explain?

Thank you!

Isaac Wen
Posts: 58
Joined: Wed Sep 30, 2020 9:35 pm
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### Re: 2F.2 Conceptual Textbook Question

I'm not entirely sure but I feel like the signs might be referring to the displacement of the electron waves. So when an electron in an orbital with a + sign meets another electron in an orbital with a + sign, constructive interference occurs. On the other hand, when an electron in an orbital with a + sign meets another electron in an orbital with a - sign, destructive interference occurs.