  The local atomic structure and lattice dynamics of two isostructural layered
transition metal dichalcogenides (TMDs), 1T-TiSe$_2$ and 1T-VSe$_2$, were
studied using temperature-dependent X-ray absorption spectroscopy at the Ti, V,
and Se K-edges. Analysis of the extended X-ray absorption fine structure
(EXAFS) spectra, employing reverse Monte Carlo (RMC) simulations, enabled
tracking the temperature evolution of the local environment in the range of
10-300 K. The atomic coordinates derived from the final atomic configurations
were used to calculate the partial radial distribution functions (RDFs) and the
mean-square relative displacement (MSRD) factors for the first ten coordination
shells around the absorbing atoms. Characteristic Einstein frequencies and
effective force constants were determined for Ti-Se, Ti-Ti, V-Se, V-V, and
Se-Se atom pairs from the temperature dependencies of MSRDs. The obtained
results reveal differences in the temperature evolution of lattice dynamics and
the strengths of intralayer and interlayer interactions in TiSe$_2$ and
VSe$_2$.
