" /> " /> " /> unusual in that Ce layers have 1/3 of the Ce atoms replaced by groups of three Ga atoms. Weak diffuse scattering suggests that disorder arises from a lack of registration of successive Ce2Ga3 layers. unusual in that Ce layers have 1/3 of the Ce atoms replaced by groups of three Ga atoms. Weak diffuse scattering suggests that disorder arises from a lack of registration of successive Ce2Ga3 layers. unusual in that Ce layers have 1/3 of the Ce atoms replaced by groups of three Ga atoms. Weak diffuse scattering suggests that disorder arises from a lack of registration of successive Ce2Ga3 layers.