Probing the valence transition in Ce <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si110.svg" display="inline" id="d1e1287"> <mml:msub> <mml:mrow/> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> </mml:math> Rh <mml:math xmln

We have investigated the behaviour of site-selective substitution in the intermetallic compound Ce 2 Rh 2 Ga which has coinciding crystal structure and valence transitions at T t = 128 . 5 K, by means of magnetic susceptibility and specific heat. Substitutions were performed on each of the Ce, Rh, and Ga sites to a level of 10 at . % . All the substituted samples proved to crystallize at room temperature in the expected orthorhombic La 2 Ni 3 -type ( C m c e , nr. 64), demonstrating the structural robustness of the host lattice upon doping. In only two of the compounds, namely Ce 1.8 La 0.2 Rh 2 Ga and Ce 2 Rh 2 Ga 0.9 Al 0.1 was the transition at T t found to disappear. • Sensitive nature of the coinciding valence- and crystal structure transition in Ce 2 Rh 2 Ga upon doping. • Hole doping in Ce as a relief valve for valence/structure transition. • Heavy effective electron mass across the doping series.