Quantum chemistry is the branch of chemistry that uses the principles and mathematics of quantum mechanics to study and explain the behavior of atoms and molecules.
It deals with how electrons are arranged in atoms and molecules, how chemical bonds form, and how energy is distributed at the microscopic level. Instead of relying only on classical physics, quantum chemistry uses wave functions, probability, and energy quantization to describe chemical systems accurately.
Key points about quantum chemistry:
- Foundation: Based on quantum mechanics (Schrödinger equation, Heisenberg uncertainty principle, etc.).
- Focus: Explains electronic structure, molecular geometry, bonding, and reactivity.
- Tools: Involves advanced mathematics, computational simulations, and approximations (like Hartree–Fock and Density Functional Theory).
- Applications:
- Predicting molecular shapes and properties.
- Understanding reaction mechanisms.
- Designing new materials, catalysts, and drugs.
- Explaining spectroscopy (interaction of light and matter).
In short, quantum chemistry connects physics and chemistry, giving us a microscopic picture of why molecules behave the way they do.