Figure 4. Nanodroplets.

Platinum–arsenic-enriched globules in equilibrium monosulphide from run Pt50As, quenched from 1,180 °C. (a) A back scattered electron (BSE) image of a polished surface intersecting five bright nano-sized Pt–As-rich globules in monosulphide; the dark cavities are filled at run conditions with S₂ vapour; scale bar, 5 μm. (b) Bright field (BF) image of a 900 by 500 nm-sized globule, with dark Pt-rich quench phases aligned in an As-bearing FeS matrix; scale bar, 100 nm. (c) BF image of the lower left of the globule in more detail; scale bar, 50 nm. (d) Absorption contrasts at the globule–matrix contact (position marked with an arrow in Fig. 3b); bright subhedral Pt–Fe-rich quench phases (Pt–Fe and PtAs₂) in a grey matrix of As-bearing FeS. Note the sharp contact between As-bearing FeS globule–matrix and As-free FeS outside the globule, window analysed in TEM scanning mode for composition marked by square; scale bar, 20 nm. (e,f) HRTEM images of the As-bearing FeS matrix inside the globule (d) and the monosulphide hosting the globule (e); both lattices are in structural continuity; scale bar, 5 nm. (g) Diffraction pattern of the Pt–As-bearing globule in (b); the As-bearing FeS matrix inside the globule is in structural continuity with the FeS surrounding the globule; the Debye–Scherrer rings (arrows) are from polycrystalline Pt-rich quench phases.