Experimental Corroboration of Lifshitz Theory

The modern formulation for van der Waals forces as originally given by LIFSHITZ [5.31] has been corroborated in a number of experiments. The first of these was described by DERJAGUIN et al. [5.56], In their measurements, the attractive force between a plate and a spherical lens, both of fused quartz, were determined for distances of separation of 100-1000 nm by use of a beam balance method. The data, from this experiment definitively established that the summation of individual molecular interactions method using either the London or Casimir and Polder interactions is inadequate to explain the data, while the Lifshitz method in the re- 

The most impressive confirmation of the theory comes from two sets of experiments reported in the early 1970s [5.60,61]. In both cases, determinations of the van der Waa1s forces covering both nonretarded and retarded distances of separation were made. The significance of such measurements is that they checked the calculations on a single system at all separations, thereby establishing the full theory rather than an asymptotic form of it. 

SABISKY and ANDERSON 5.61 used an acoustic method to monitor the thickness as a function of height of a liquid helium film adhering to a SrF2 cleaved surface. They found complete agreement between their data and Lifshitz theory over the entire range of thicknesses 1-25 nm they measured. 

SHIH [5.62] and SHIH and PARAI6IAN [5.63] measured and discussed the van der Waals forces between alkali atoms and a vacuum-deposited gold surface. Though 

ISRAELACHYILI and TABOR [5.65] provide a further review of the experimental literature (as well as of van der Waals forces in general) and DONNERS et al. 

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