检测固体的表面自由能至少需要三种液体：一种纯色散液体，两种已知酸碱部分的液体。其中至少一种液体极性部分大于0。作为路易斯中性，水需要在所有测试中使用。
参考文献
- R. J. Good; C. J. van Oss, The Modern Theory of Contact Angles and the Hydrogen bond Components of Surface Energies. In: G. I. Loeb; M. E. Schrader (Hrg.): Modern approaches to wettability. 1992, P. 1-27.
- R. J. Good, Contact Angle, Wetting and Adhesion: a Critical Review. In: K. L. Mittal (Hrg.): Contact Angle, Wettability and Adhesion. Festschrift in Honor of Professor Robert J. Good. Utrecht 1993, P. 3-36.
- C. J. van Oss; M. K. Chaudhury; R. J. Good, Interfacial Lifschitz-van der Waals and Polar Interactions in Macroscopic Systems. In: J. Chem. Rev. 88 (1988), P. 927-941.
