Question

Explain Molecular Orbitals theory ?

Answer 1

Answer:

The Molecular Orbital Theory is a method for describing the electronic structures of molecules using quantum mechanics...

Electrons are not assigned to individual bonds between atoms, but are treated as moving under the influence of nuclei in the whole molecule...

Hope it helps...✌️✌️✌️

Answer 2

Answer :-

★ Molecular Orbital (MO) Theory was developed by F. Hund and R. S. Mulliken in 1932. The salient features of this theory are :-

✏ The electrons in a molecule are present in the various molecular orbitals, as the electrons of atoms are present in the various atomic orbitals.

✏ The atomic orbitals of comparable energies and proper symmetry combine to form molecular orbitals.

✏ While an electron in an atomic orbital is influenced by one nucleus, in a molecular orbital it is influenced by two or more nuclei depending upon the number of atoms in the molecule. Thus an atomic orbital is monocentric while a molecular orbital is polycentric.

✏ The number of molecular orbital formed is equal to the number of combining atomic orbitals. When the two atomic orbitals combine, two molecular orbitals are formed. One is known as Bonding Molecular Orbital while the other is known as Anti - Bonding Molecular Orbital.

✏ The bonding molecular orbital has lower energy and hence greater stability than the corresponding anti bonding molecular orbital.

✏ Just as an electron probability distribution around the nucleus is given by an atomic orbital, the electron probability distribution around a group of nuclei in a molecule is given by a molecular orbital.

✏ The molecular orbitals like atomic orbitals are filled in accordance with the Aufbau principle obeying the Pauli's exclusion principle and the Hund's Rule.

★ Aid to Memory :-

• According to wave mechanics, the atomic orbitals can be expressed by wave functions which represent the amplitude of the electron waves.

• These are obtained from the solution of Schrôdinger's Wave Equation.

• The molecular orbital formed (sigma / pi) by the addition of atomic orbitals is called bonding molecular orbital.

• The molecular orbital formed (sigma / pi)* by rye subtraction of atomic orbitals is called anti - bonding molecular orbital.