Department of Chemistry, Faculty of sciences, Guilan University, P.O. Box: 41335-1914, Rasht, Iran
Department of Chemistry, Payame Noor University, P. O. Box 19395-3697, Tehran, Iran
Sulfamic acids are very important compounds with a little consideration in the literature that have wide range of applications in our life. Various N-alkyl and N-cycloalkyl sulfamic acids selected and their acidity was calculated in gas and aqueous media. pkavalues obtained with the use of two thermodynamic cycles that differ in the reference molecule which were used with them. Obtained pka values show strong acidity for sulfamic acids. We used density functional theory for all calculations.