IN a letter to NATURE of November 25 last Dr. Norman Campbell discusses the problem of the possible consistency of the assumptions about the motion and arrangement of electrons in the atom ...

The relative charge of a nucleus is the same as its proton (atomic ... charged ion if the atom gains one or more electrons, it becomes a negatively-charged ion A helium atom has two electrons ...

For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass, it seemed that something besides the protons in the nucleus ...

Researchers have taken atomic diffraction to ... The single-layer graphene, just one atom thick, proved to be an ideal platform for this effect. Its uniform structure allowed precise diffraction ...

For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass, it seemed that something besides the protons in the nucleus ...