In the present research, the temperature dependence of heat capacity C-p,C-m degrees = integral(T) of neopentylbenzene C6H5-C5H11 has been measured between T = (6 and 350) K in the precision adiabatic vacuum calorimeter and reported for the first time. The temperature and enthalpy of fusion of neopentylbenzene and the total mole fraction of impurities have been determined. The experimental results have been used to calculate the standard (p degrees = 0.1 MPa) thermodynamic functions C-p,C-m degrees/R, Delta H-T(0)m degrees/RT, Delta S-T(0)m degrees/R and Phi(m)degrees/R = Delta S-T(0)m degrees/R-Delta H-T(0)m degrees/RT (where R is the universal gas constant) of neopentylbenzene over the range from T -> (0 to 350) K. The standard entropy of formation of the compound under study at T = 298.15 K has been calculated. (C) 2011 Elsevier Ltd. All rights reserved.