Dear Sir,
Further to our comments above, we will like to add the following.
In Coulomb's law, F = k Q1 x Q2 /d^2. In a charge neutral object, either Q1 or Q2 will be zero reducing the whole equation to zero. This implies that no interaction is possible between a charged object and a charge neutral object. But this is contrary to experience. Hence the format of Coulomb's law is wrong.
When we said "positive positive = explosive", what we meant was the fusion reaction tat leads to unleashing of huge amounts of energy. Its opposite is also true, but since it is reduction, there is less energy release.
Positive negative (total interaction) = internally creative (increased atomic number.) This means that if one proton and one electron is added to the atom, the atomic number goes up.
Positive negative (partial interaction) = externally creative (becomes an ion.) This means that if one proton or one electron is added to the atom, the atom becomes ionic.
Negative negative = no reaction. What actually it means that though there will be no reaction between the two negatively charged particles; they will appear to repel each other as their nature is confinement. Like two pots that confine water cannot occupy the same place and if one is placed near another with some areas overlapping, then both repel each other. This is shown in the "Wheeler's Aharonov-Bohm experiment".
Regards,
basudeba