Rep1 contained no information about the properties of the elements present in the material. Due to this, it was difficult for our model to learn the properties of the compound, which depend on the elemental properties, e.g. formation energy, as discussed in section 3.1. Therefore, the properties of the elements present at each site were also added to the representation. The elemental properties were one-hot encoded. When working with generative models, it is better to have dimensions whose interdependencies are not complex, which is why we believe one hot encoding makes the process of learning easier for the encoder.