Scattering of X-Rays in Liquids

The method which gives the clearest insight into the conditions prevailing is the scattering of x-rays in liquids this will be briefly discussed below. 

to whom, particularly, we owe the clear recognition and calculation of the two effects, has named them inner and outer interference. 

The inner diffraction effect is produced when the individual particles of the atom capable of vibration, i.e. the electrons contained in the atoms, are dispersed and give rise to secondary radiations which interfere with one another. In a liquid built up of single atoms— A, Kr, Xe, Hg, Ga— the result is that, on account of intra-atomic interference, the dependence of intensity distribution on the angle of diffraction is already affected. This influence is generally expressed by a factor, which, because of its origin, is called the atomic form factor its action is that more intensity is scattered in the directions near the primary beam than if the interaction of the individual electrons is not taken into account. 

If we are concerned with a molecule composed of several atoms— H2O, CCI4, CeHe etc.— we have to imagine that the individual atoms, which have definite positions in the molecule, also send out secondary waves which interfere with one another and cause a further change of the angular dependence of the scattered radiation intramolecular inter- 

The internal effect is clearest in the scattering of x-rays or electrons by molecules in the gaseous state and its study in the gas phase has provided the very interesting evidence on molecular structure which has already been discussed in the first section.  

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