Processes in Isotopes and Molecules (PIM 2021), 22-24 September 2021, Cluj-Napoca, Romania

It is our pleasure to introduce a special issue of Analytical Letters comprising selected papers presented at the 13th edition of International Conference on Processes in Isotopes and Molecules (PIM 2021) held between 22 and 24 September 2021 and organized by the National Institute for Research and Development of Isotopic and Molecular Technologies in Cluj-Napoca, Romania. The Conference brought together scientists from academia, research institutes, and industry to discuss their latest results. The scientific program was completed by exhibitors presenting latest equipment and services in the field of molecular and isotopic sciences. The PIM 2021 conference promotes the exchange of ideas, experience and knowledge between scientists and engineers, as well as to encourage collaborative interdisciplinary research activities. PIM 2021 provided a stimulating communication and discussion platform in a wide range of topics from fundamentals in physics and chemistry, to applied research on energy efficiency, environment, materials and isotopic technologies.