Additional helium atoms can attach to HeH to form larger clusters such as HeH, HeH, HeH, HeH and HeH.
The dihelium hydride cation, HeH, is formed by the reaction of dihelium cation with molecular hydrogen:
:  + H → HeH + H
It is a linear ion with hydrogen in the centre.
The hexahelium hydride ion, HeH, is particularly stable.
Other helium hydride ions are known or have been studied theoretically. Helium dihydride ion, or dihydridohelium(1+), , has been observed using microwave spectroscopy. It has a calculated binding energy of 25.1 kJ/mol, while trihydridohelium(1+), , has a calculated binding energy of 0.42 kJ/mol.