Interaction Type
Example Average Strength, kcal/mol (kJ/mol) Range**
Charge-charge (ionic) -NH3+ Cl-   1/r
Charge-dipole -NH3+ClCH3   1/r2
Dipole-dipole ClCH3 ClCH3    1/r3
Dipole-induced dipole* CH4 ClCH3 0.1-0.2 (0.4-4)  1/r6
Dispersion*
(induced dipole-induced dipole)
CH4 CH4

0.1-0.2 (0.4-4)
1/r6
Hydrogen bond  two H-bonded water molecules 3-8 (12-30)  

 van der Waals repulsion
    1/r12

*van der Waals interactions, **from Zubay Biochemistry 3rd. (1993) Table 4.3, pg. 89.

 

 

 

 

 

 

 

 

 

 

 

 

 

structural diagram of carboxylate, alcohol, amine, thiol, phnol and imidazole functional groups.

 

 

 

Last modified 31 January 2010

© RA Paselk 2001