What kind of illumination to use to produce these 3D ball-and-stick atomic structure models? (specular reflection but no shadows) I'd like to render a publication quality image something like the image below. I'll script the whole process so we can build many different structures without having to redraw everything, and probably animate it as well.
I'll want to be able to rotate the camera and the light source independently to view from any angle, so I need some kind of illumination/shader combination that keeps the whole sphere well diffusely lit no mater where the &quot;Sun&quot; is placed.
They all seem to have a similar diffuse shader with some specular component; we can see the reflection of a narrow light source or Sun on every atom, but they don't shadow each other, and there is some source of diffuse illumination as well, there's no night/dark line where &quot;the Sun don't shine&quot; i.e. on the very bottom-right edge.
Question: What kind of illumination and/or shader use to produce these 3D ball-and-stick atomic structure models that show specular reflection but don't have shadows, and will be viewable from any direction?
To maintain flexibility/compatibility with future projects I'm assuming I should ask for a solution for the cycles rendering engine, but I supposed I can be talked out of it.

Phys.org' Electrons falling flat: Germanium falls into a 2-D arrangement on zirconium diboride shows a ball-and-stick model of a somewhat complicated 3D arrangement of atoms.
The blue atoms are germanium (light blue ones stick up above the others), green is zirconium and orange are boron.
A few steps that might help Cycles render like this:
Lighting:
I find it's usually best to adjust this first, on neutral-grey surfaces
A single key point-light, with ambient fill provided by a somewhat luminous World. The World has one color to contribute to the lighting, and another to appear in the camera, thus:

The size of the point-light will affect the size and softness of the 'ping' specular dot on the spheres.
Object visibility:
You've got to cripple Cycles on the objects, to prevent shadows being cast, and stop any diffuse bounce of light between them. Switching off everything bar 'Camera' visibility seems to work, in the Object Properties tab &gt; Visibility panel:

Materials:
For convenience, a Principled shader:

.. with 'Roughness' adjusting size and softness of highlight, and maybe a tweak of 'Specular' intensity. A tiny contribution of 'Emission' in the base color, helps the World fill the away-from-light surfaces.
This sort of result: