Debye (D) Definition:
The Debye (D) is a unit of measure for dipole moments. 1 debye = 10-18 esu × cm.
Debye (D) Explained:
A dipole moment is given as the product of the partial charge and the distance between them. Partial charges are generally on the order of 10-10 esu while the distance between them is generally 10-8. therefore a dipole moment generally has an order of magnitude 10-18, unit esu cm or 1 debye (D).
For example, 1.87 x 10-18 is then written or considered as 1.87 D. Measuring a Dipole unit in a compound allows us to know the ionic characteristic of a bond.