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Negative Hydrogen Ions in Cyclotrons and elsewhere
I was vaguely aware that negative hydrogen ions are used in some cyclotrons and this improves beam current.
I've been thinking about this recently after noting that hydrogen is actually quite electronegative in comparison to most metals (just less electronegative than oxygen and other things it tends to bind with).
So, presumably, if you mix hydrogen gas with electrons in a vacuum then they will tend to make H2- molecular ions. Is that right?
It sets me wondering on a few things.
Presumably, the energy of a H2- ion is +13eV?
Does it radiate the Balmer series of photons as a second electron falls into that first shell, and does anything else happen if it let's an electron go?
What is the activation energy needed to prompt it to shed the electron?
If hydrogen molecules and electrons are floating around in a vacuum with, say, 1eV electrons, do they tend to form H-, H2-, H3- and if all of the above, then what is the relative proportion of species?
Presumably if H2- meets more electrons it might break up and form two H- ions?
I can't find any texts at all about this, so if there is something then please let me know.
I was vaguely aware that negative hydrogen ions are used in some cyclotrons and this improves beam current.
I've been thinking about this recently after noting that hydrogen is actually quite electronegative in comparison to most metals (just less electronegative than oxygen and other things it tends to bind with).
So, presumably, if you mix hydrogen gas with electrons in a vacuum then they will tend to make H2- molecular ions. Is that right?
It sets me wondering on a few things.
Presumably, the energy of a H2- ion is +13eV?
Does it radiate the Balmer series of photons as a second electron falls into that first shell, and does anything else happen if it let's an electron go?
What is the activation energy needed to prompt it to shed the electron?
If hydrogen molecules and electrons are floating around in a vacuum with, say, 1eV electrons, do they tend to form H-, H2-, H3- and if all of the above, then what is the relative proportion of species?
Presumably if H2- meets more electrons it might break up and form two H- ions?
I can't find any texts at all about this, so if there is something then please let me know.