The thermal expansion of europium fluoride(EuF2)has been measured with a push‐rod dilatometer. Over the range 25°C–200°C the expansion coefficient is given by&agr; = 14.23 × 10−6 −0.007 × 10−8 t + 2.88 × 10−10 t2where t is the temperature in °C. The thermal Gruneisen constant has a value 1.17 while a calculation based on an ionic model gives a value of 1.64 for the Gruneisen constant.