Reply to Doster: Franck–Condon and Van Hove formulation of quasielastic neutron scattering from complex systems

Doster (1) criticizes a number of points in ref. 2, where a Franck–Condon-type spectroscopic formulation of incoherent neutron scattering is presented. My responses are given below.First, the Franck–Condon formulation of incoherent neutron scattering does not contradict standard scattering theory, and it is even based on it. It merely starts from a nonstandard form of the intermediate scattering function, which is (probably) due to Wick (3), instead from the usual form that appears in the well-known paper by Van Hove (4). As long as the Van Hove form is considered in the quantum regime, both forms are completely equivalent. The two textbook models are presented to … [↵][1]1Email: gerald.kneller{at}cnrs.fr. [1]: #xref-corresp-1-1