  Detailed experimental investigations of thermal and magnetic properties are
presented for Cu(NH3)4SO4.H2O, an ideal uniform Heisenberg spin half chain
compound. A comparison of these properties with relevant spin models is also
presented. The temperature dependent magnetic susceptibility and specific heat
data has been compared with the exact solution for uniform Heisenberg chain
model derived by means of Bethe ansatz technique. Field dependent isothermal
magnetization curves are simulated by Quantum Monte Carlo technique and
compared with the corresponding experimental ones. Specific heat as a function
of magnetic field (up to 7T) and temperature (down to 2K) is reported.
Subsequently, the data are compared with the corresponding theoretical curves
for the infinite Heisenberg spin half chain model with J=6K. Moreover, internal
energy and entropy are calculated by analyzing the experimental specific heat
data. Magnetic field and temperature dependent behavior of entropy and internal
energy are in good agreement with the theoretical predictions.
