Fig.2.

Frozen-hydrated influenza virus over graphene. (a) Low magnification image of a grid square with 3 μm diameter holes covered by amorphous ice and empty holes. (b) Sections of a tomogram (24 nm thick) parallel to the plane of the amorphous ice with influenza virions. (c) Sections of a tomogram (13 nm thick) perpendicular to the plane of the ice along the dotted line in b. (d) Diffraction pattern shows hexagonal graphene reflections at 2.13 Å (red arrows) and diffuse amorphous ice rings (blue arcs at 3.7 Å and 2.14 Å resolution). (inset) Radial average of the pattern within a sector that excludes graphene reflections (as indicated by arcs along amorphous ice maxima) with first ice maximum (dotted vertical line) and the resolution of graphene reflections (2.13 Å, vertical red line) indicated. Horizontal arrow shows region obscured by beamstop. Scale bars 100 nm.