What is the SI unit of dipole moment?

The SI unit of electric dipole moment is the coulomb-metre (C·m). The electric dipole moment is a measure of the separation of positive and negative charges in a system. It is a vector quantity defined as μ = q × d, where q is the magnitude of charge and d is the separation distance between charges. The SI derived unit is the coulomb-metre (C·m). 

• In chemistry, a common unit for molecular dipole moment is the Debye (D). 1 D ≈ 3.33564 × 10⁻³⁰ C·m.
• Direction: The dipole moment vector points from the negative charge toward the positive charge (in physics convention) or vice versa in some chemical contexts.

Why important:

• Dipole moment helps predict molecular behaviour in electric fields, solubility, polarity, intermolecular forces.
• In spectroscopy and quantum chemistry it is a fundamental property of molecules.