Question

Which of the following forces contribute to stability of charge transfer complexes?

• A. \( \text{Resonance forces} \)
• B. \( \text{Resonance and London dispersion forces} \)
• C. \( \text{Dipole-dipole interactions and London dispersion forces} \)
• D. \( \text{Resonance forces and dipole-dipole interactions} \)

Hint:

Remember that charge transfer implies electronic interaction (resonance), and all molecules experience London dispersion forces.

Answer 1

The Correct Option is B

Charge transfer complexes are stabilized by a combination of intermolecular forces. These include: 1. Resonance forces (Charge-transfer forces): These arise from the partial transfer of electronic charge from the donor molecule to the acceptor molecule, creating a weak covalent interaction and contributing significantly to the stability. 2. London dispersion forces: These are weak intermolecular forces arising from temporary dipoles induced in the electron clouds of the molecules and are always present, contributing to the overall stabilization. 3. Dipole-dipole interactions: If the donor or acceptor molecules (or both) are polar, dipole-dipole interactions can also contribute to the stability of the complex. 4. Electrostatic forces: These arise from the attraction between the partially positive and partially negative centers created by the charge transfer. Considering the options, the most comprehensive and accurate answer includes both resonance forces (which are fundamental to the nature of charge transfer) and London dispersion forces (which are always present and contribute to intermolecular interactions). While dipole-dipole interactions and electrostatic forces are also involved, resonance and London dispersion forces are the most consistently significant contributors to the stability of a wide range of charge transfer complexes.