Why is the ABMO more destabilized then BMO is stabilized

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In summary, the antibonding molecular orbital is more destabilized than the bonding molecular orbital due to the normalization of the molecular orbitals, where the anti-bonding orbital is normalized with a minus sign and has a smaller value than the bonding orbital. This results in the anti-bond being more destabilized than the bond is stabilized due to the exchange energy.
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hivesaeed4
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When we mix the atomic orbitals of two atoms, why is it that the antibonding molecular orbital is more destabilized than the bonding molecular orbital is stabilized. Note that the two atoms are different atoms.
 
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That's mainly due to the normalization of the molecular orbitals.
The bonding/non-bonding orbitals are normalized as [itex]\psi_\pm=\frac{1}{\sqrt{2}(1\pm S)}(\phi_A\pm \phi_B)[/itex] where [itex] S=\langle B|A \rangle [/itex] where the plus sign refers to bonding and the minus sign to the anti-bonding orbital.
With the exchange energy [itex] H_{AB}=\langle B|H|A\rangle [/itex] the bonding energies are approximately [itex] E_\pm\approx \pm H_{AB}/(1\pm S)[/itex]. Now with 1-S being much smaller than 1+S, the anti-bond is more destabilzed than the bond is stabilized.
 

What is ABMO and BMO?

ABMO and BMO stand for anti-bonding molecular orbital and bonding molecular orbital, respectively. They are quantum mechanical concepts used to describe the electron distribution and stability of molecules.

Why is the ABMO more destabilized than BMO?

The ABMO is more destabilized than BMO because it has a higher energy level and a larger electron density at the antibonding region. This means that the electrons in the ABMO are less tightly bound to the nucleus, making the molecule less stable overall.

How does the stability of a molecule relate to its ABMO and BMO?

The stability of a molecule is directly related to the energy levels and electron distribution of its ABMO and BMO. A molecule with a lower energy ABMO and a higher energy BMO will be more stable, while a molecule with a higher energy ABMO and a lower energy BMO will be less stable.

What factors influence the stability of ABMO and BMO?

The stability of ABMO and BMO is influenced by the types of atoms in the molecule, their arrangement, and the strength of their bonding interactions. The electronegativity of the atoms also plays a role, with atoms with higher electronegativity contributing to a more stable BMO.

How is the concept of ABMO and BMO used in chemistry?

The concept of ABMO and BMO is important in understanding chemical bonding and the stability of molecules. It helps predict the reactivity and properties of different molecules and is used in fields such as organic chemistry, biochemistry, and materials science.

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