Theoretical calculations and experimental measurements have been made to look for reported chemical dependence in the yield of delayed neutrons from thermal-neutron-induced fission in 235U. Using an Einstein model of the lattice phonon distribution, calculations have been made that indicate no significant dependence of the fission cross section on the lattice phonon distribution. Two types of experimental measurements were made. The fission fragment yield was compared for thermal-neutron-induced fission in U3O8 and UO2. The delayed neutron yields from U3O8 and UO2 were also compared. In neither measurement was there a significant difference in yield for the two chemical states of uranium.