Self-referencing embedded strings (SELFIES): A 100% robust molecular string representation

Abstract

The discovery of novel materials and functional molecules can help to solve some of society’s most urgent challenges, ranging from efficient energy harvesting and storage to uncovering novel pharmaceutical drug candidates. Traditionally matter engineering–generally denoted as inverse design–was based massively on human intuition and high-throughput virtual screening. The last few years have seen the emergence of significant interest in computer-inspired designs based on evolutionary or deep learning methods. The major challenge here is that the standard strings molecular representation SMILES shows substantial weaknesses in that task because large fractions of strings do not correspond to valid molecules. Here, we solve this problem at a fundamental level and introduce SELFIES (SELF-referencIng Embedded Strings), a string-based representation of molecules which is 100% robust. Every SELFIES string corresponds to a valid molecule, and SELFIES can represent every molecule. SELFIES can be directly applied in arbitrary machine learning models without the adaptation of the models; each of the generated molecule candidates is valid. In our experiments, the model’s internal memory stores two orders of magnitude more diverse molecules than a similar test with SMILES. Furthermore, as all molecules are valid, it allows for explanation and interpretation of the internal working of the generative models.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 28, 2020
Source ID
10.1088/2632-2153/aba947

Entities

People

  • AkshatKumar Nigam
  • Alán Aspuru-Guzik
  • Florian Häse
  • Mario Krenn
  • Pascal Friederich

Organizations

  • Austrian Science Fund
  • Office of Naval Research

Tags

Readers

  • Computational Linguistics
  • Distributed Systems and Data Platform Development
  • Molecular Genetics

Technology Areas

  • AI & ML