As hyper says, allotropes are probably what you mean. You could look 'em up in Wikipedia.(Sulfur has some funny Allotropes!)
mass of H3? I don't think that's quite a stable molecule. It's collapse as fast as being generated.
Wiki says the range is ~0.7-2.5 fm. However 1 fm is the most powerful.
It's force depends on the nuclei involved, their distance and their number. This image will do it:
Force (in units of 10,000 N) between two nucleons that experience the nuclear force, as a function of distance. In the graph that falls below the horizontal axis, the spins of the particles (which must be different, such as a neutron and proton) are aligned, and they become bound with a negative "binding energy," which becomes maximal at a distance a little more than 1 fm at the minimum of the region shown. Particles much closer than this optimal distance experience a repulsive force. Particles farther than the distance of highest attractive force still experience a smaller attractive potential (Yukawa potential), but it falls at an exponential function of distance.
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