Using density functional theory calculations, we report on the adsorption of methylamine on gold and compare its adsorption to a selection of alkylamines, methanol and methanethiol. On the (111) surface, the amines, thiol and alcohol bind in the ontop site with a preference over hollow and bridge sites of 0.3 eV, 0.2 eV and 0.1 eV for methylamine, methanethiol and methanol, respectively. The effect of steps is considered on the (211) surface of gold and we find that methylamine adsorbs 0.2 eV more strongly in the step ontop site of the surface than on the (111) surface. For oxygen atom pre-coverages of 0.04-0.25 ML on the (111) surface, we find cooperative adsorption of amines and oxygen atoms. The energetic costs of adsorbate tilt from the surface normal and of rotation about the gold-heteroatom bond are compared among the studied surfaces and conditions.

Our experimental and theoretical investigation focuses on the role of magnetism on the structures and energetics of nanoclusters of the important 3d antiferromagnetic (AFM) semiconductor, manganese sulphide (MnS). Our cluster beam mass spectra for both (MnS) n and (MnSe) n show a pronounced "magic" abundance, at n = 13, in accord with results for other nonmagnetic chalcogenide clusters (e.g., CdS, CdSe, ZnS, ZnSe). Using global optimization and ab initio calculations we focus on cluster isomers of (MnS) 13 and its two neighboring compositions, (MnS) 12 and (MnS) 14 , and show that the magic status of the former is fully compatible with the high relative energetic stability of the n = 13 ground state with respect to those for n ± 1. We demonstrate a strong symbiosis between cluster structure and spin ordering, which leads to a particular type of AFM spin-ordered ground-state cluster structure being energetically selected for all cluster sizes and which enhances the magic stability of (MnS) 13 . This nanomagnetostructural effect highlights a fundamental link between magnetism and cluster structure having potential implications for (nano)technologies based on magnetostructural transitions (e.g., data storage, magnetic refrigeration).

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