Space-filling molecular models: Halogen expansion set

cults3d

The halogens are one of the best reasons for using space-filling models. With ball-and-stick models and especially writing structures on paper, you can easily convince yourself that all the atoms are about the same size. With most of the halogens, this decidedly doesn't apply. Most of them are several times larger than carbon or nitrogen. Granted they are further down the periodic table so you would expect them to be larger, but it's still surprising how much larger they are. "Are they really that weird shape?" I hear you ask. Probably not; we don't know exactly what they look like. They are probably more spherical, but they can crowd nearby atoms so some allowances are made. "I thought one of the points of space-filling models was to tell when things get too close together." True, but they don't crowd other atoms that much, and atomic orbitals seem to be more compliant than ABS (it would be interesting to try using flexible filament). Bromine is traditionally brown but I didn't have any brown filament (and I think I like it in gold).