In the Young equation, only two of the four unknowns are measurable. They are the liquid interfacial tension sigma(lv) and the contact angle theta. To solve this equation, another correlation is required. In solving this equation, a better understanding of the magnitude of the solid interfacial tension sigma(sv) and the solid-liquid interfacial tension sigma(sl) is expected. The possibility of a theoretical estimation of the contact angle theta is sought as an alternative to the experimental method. In this paper, an attempt to calculate the solid interfacial tension sigma(sv) is reported. It is based on the intermolecular interaction which is mathematically described in the parameter Phi(sl) according to Good. The calculated sigma(sv) values for PTFE, steel, and glass surrounded by dense carbon dioxide are verified by comparing those values obtained from aqueous and ethanolic systems. Furthermore, the solid interfacial tension sigma(sv) is also used to forecast the water drop contact angle theta. The calculated values are compared with the experimental measured ones. (C) 2007 Elsevier Inc. All rights reserved.