Other works have focused on optimizing the structure of nanoparticles (NPs). Finding structures that are the GM, or lie close enough energetically to be accessible from the GM, is particularly important in NP structures such as nanoalloys and nanocatalysts as small changes in the structures/atomic composition of these materials have large impacts on their physical and chemical properties. The necessity for high quality, well-sampled ensembles of geometrically unique low energy structures (ULES) is heightened when considering the catalytic processes of nanocatalysts at operating temperatures. Higher temperatures often increase the relative population presence of low lying LMs therefore to construct a realistic ensemble the low lying energies should be well sampled. Further to this entropic terms should also be considered. Configurational entropy is a particularly important factor in the thermodynamics of catalytic systems. Understanding the configurational landscape also allows for a prediction of the most probable reaction pathways. In this work, we employ swarm intelligence to generate structures for the H 2 adsorption on Pt NPs. We select this process because it has been studied extensively and therefore provides an excellent example system to compare the competency of our algorithm. Beyond being a good system to benchmark against, H adsorbed on to Pt NPs is a relevant system in heterogeneous catalysis. Surface coverage plays an important role in gas adsorption. Consequently, we assess its effect on adsorption by performing simulations under varying NP surface coverage both before and after the H 2 bond cleavage. Previously, Tan et al. used density functional theory (DFT) calculations and microkinetic modelling to estimate energy barriers of H* adsorbed onto a perfect Pt NP. They found that (100)-facet bridge site pairs are kinetically favored as they present the lowest activation energy. Fujita et al. used extended X-ray absorption fine structure (EXAFS) found a linear relationship between the amount of adsorbed hydrogen and Pt-Pt distance. Furthermore, Aguilera-Porta et al. used transmission electron microscopy (TEM) to follow the formation of Pt NPs. They found that the presence of hydrogen considerably affects both their shape and size during synthesis. Consequently, experiment shows that hydrogen adsorption considerably affects the shape of Pt NPs. Parker et al. postulate that experimental and computational works agree that most of the adsorbed hydrogen is placed in two-fold bridging sites. These works provide several key metrics to assess the quality of the structures we produce. Specifically, we will compare against • H adsorption energy onto a Pt NP: multiple estimates of the H adsorption energy have been made in both experimental and theoretical literature (c.f table ), while no exact readings for our systems have been made we would expect to be within range of previously reported readings (-0.3 to -0.8 eV).