Regarding the validity rate of each model, we sampled 1000 latent vectors from a Gaussian distribution N(0,1) and decoded each vector into a SMILES and subsequently used the RDKit software to parse the SMILES into molecules and assess whether the generated SMILES are syntactically valid. As validity rate, we report the ratio of valid decoded molecules in the 1000 sampled molecules. A more thorough analysis of the VAE performance for different annealing schedules is included in the SI (section S1.3).