Sci-Fi weapons: Isomer Bombs

The best place to find a Sci-Fi weapon is in the R&D labs where ideas have more often than not, failed.

Mystery and uncertainty surrounds the results of a test performed in an attempt to create a gamma radiation explosion using an nuclear isomer of Hafnium 178m2. The idea was to put a small amount of energy in and get a lot of gamma radiation out. This isomer bomb turns out to have an energy conservation problem. It's a classic energy storage problem where the energy released needs to be put there in the first place (I think of the silly idea of using Hydrogen as a transport fuel).

What a diabolical Sci-Fi weapon - an Isomer Radiation Bomb.