Scattered intensity in the limit of zero concentration intra- and intermolecular structure functions

2 Scattered intensity in the limit of zero concentration intra- and intermolecular structure functions 

The mean form function of a chain is obtained from scattering experiments on dilute solutions, by extrapolation at zero concentration [see (15.1.10)], 

This function is by definition normalized to unity for q = 0. The significant reciprocal space interval for Hz(q), is (0,1/1,) where 1, is the interatomic distance. Radiation scattering allows us to explore the intervals (see Chapter 6, Fig. 6.4, p. 234) 

Therefore, in order to determine the form function Hz(q) of a sample in the largest possible interval, one has in general to perform two experiments, using a different type of radiation in each case. 

however, possible to produce samples for which a unique light scattering experiment enables the experimentalist to explore the three characteristic ranges  

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