  The results of EXAFS measurements at 300 K for the superconducting compounds
Tl$_{0.75}$Cu$_{0.25}$Ba$_{2}$Ca$_{3}$Cu$_4$O$_{y}$ [Tl-1234],
TlBa$_{2}$Ca$_{3}$Cu$_{4}$O$_{y}$ [Tl-1212], and
CuBa$_{2}$Ca$_{3}$Cu$_{4}$O$_{y}$ [Cu-1234]. are reported. We have measured the
EXAFS spectrum for Tl$_{0.75}$Cu$_{0.25}$Ba$_{2}$Ca$_{3}$Cu$_4$O$_{y}$ in the
range 10K-300K, however here we limit our discussion to the spectrum at 300 K.
This material is prepared under high pressure [3.5 GPa] from precursors with
small carbon concentrations and exhibits a T$_c$ of $~127$ K. We have also
performed ``aging'' study by looking at XRD for this material after
approximately one year. The XRD results at 300 K are ``unchanged''. It is of
interest to compare the EXAFS spectrum of this compound with the corresponding
compound Cu-1234. Remarks on the choice of appropriate EXAFS standard for this
and related compounds are also given. Based on our data analysis we quantify
disorder in these systems. By using the Cu-O in-plane distance we give values
for the microstrain parameter, which can be related to the charge ordering
transition.
