Evolution of three Nobel Prize themes and a Nobel snub theme in chemistry: a bibliometric study with focus on international collaboration.

In this study, three chemistry research themes closely associated with the Nobel Prize are bibliometrically analyzed-Ribozyme, Ozone and Fullerene-as well as a research theme in chemistry not associated with the Nobel Prize (a Nobel snub theme): Brunauer-Emmett-Teller equation. We analyze, based on an algorithmically constructed publication-level classification system, the evolution of the four themes with respect to publication volume and international collaboration, using two datasets, one of them a subset of highly cited publications, for each considered time period. The focus of the study is on international collaboration, where co-occurrence of country names in publications is used as a proxy for international collaboration. For all four themes, especially for Brunauer-Emmett-Teller equation, the publication volumes increase considerably from the earliest period to the later periods. The international collaboration rate shows an increasing trend for each theme. For Ozone, Fullerene and Brunauer-Emmett-Teller equation, the international collaboration rate tend to be higher for the highly cited publications compared to full datasets. With regard to the evolution of number of countries per international publication and per highly cited international publication, a vast majority of the distributions are positively skewed, with a large share of publications with two countries. With respect to the last four periods of the study, the concentration to two countries per publication is more pronounced for the Brunauer-Emmett-Teller equation theme compared to the three Nobel Prize themes.