The compound has not been isolated in pure form, although it has been the subject of several studies.

[1] Attempts to isolate Hg(OH)2 yield yellow solid HgO.

The solid has produced it by irradiating a frozen mixture of mercury, oxygen and hydrogen.

The mixture had been produced by evaporating mercury atoms at 50 °C into a gas consisting of neon, argon or deuterium (in separate experiments) plus 2 to 8% hydrogen and 0.2 to 2.0% oxygen.

The mixture was then condensed at 5 kelvins onto a caesium iodide window, through which it could be irradiated.