  Quantum phase transitions of the transverse Ising and antiferromagnetic XXZ
spin S=1/2 chains are studied using quantum discord. Quantum discord allows the
measure of quantum correlations present in many-body quantum systems. It is
shown that the amount of quantum correlations increases close to the critical
points. The observations are in agreement with the information provided by the
concurrence which measures the entanglement of the many-body system.
