This hydrogen chalcogenide is a pale yellow volatile liquid with a camphor-like odor.
[1] Hydrogen disulfide can be synthesised by cracking polysulfanes (H2Sn) according to this idealized equation: The main impurity is trisulfane (H2S3).
[1] The precursor polysulfane is produced by the reaction of hydrochloric acid with aqueous sodium polysulfide.
[3] The deuterated form of hydrogen disulfide, deuterium disulfide D−S−S−D (dideuterodisulfane), has a similar geometry to H−S−S−H, but its tunneling time is slower, making it a convenient test case for the quantum Zeno effect, in which frequent observation of a quantum system suppresses its normal evolution.
Trost and Hornberger[4] have calculated that while an isolated D−S−S−D molecule would spontaneously oscillate between left and right chiral forms with a period of 5.6 milliseconds, the presence of a small amount of inert helium gas should stabilize the chiral states, the collisions of the helium atoms in effect "observing" the molecule's momentary chirality and so suppressing spontaneous evolution to the other chiral state.