  We ascertain, following ideas of Arnesen, Bose, and Vedral concerning thermal
entanglement [Phys. Rev. Lett. {\bf 87} (2001) 017901] and using the
statistical tool called {\it entropic non-triviality} [Lamberti, Martin,
Plastino, and Rosso, Physica A {\bf 334} (2004) 119], that there is a one to
one correspondence between (i) the mixing coefficient $x$ of a Werner state, on
the one hand, and (ii) the temperature $T$ of the one-dimensional Heisenberg
two-spin chain with a magnetic field $B$ along the $z-$axis, on the other one.
This is true for each value of $B$ below a certain critical value $B_c$. The
pertinent mapping depends on the particular $B-$value one selects within such a
range.
