In the year 1931, Harold Urey discovered the isotope deuterium and was later able to concentrate it in water. Urey's mentor Gilbert Newton Lewis isolated the first sample of pure heavy water by electrolysis in 1933. George de Hevesy and Hoffer used heavy water in 1934 in one of the first biological tracer experiments, to estimate the rate of turnover of water in the human body. The history of large-quantity production and use of heavy water in early nuclear experiments is given below.

EPA Genetic Toxicology Program. Reported in EPA TSCA Inventory.

The Heavy water with CAS registry number of 7789-20-0 is also known as Deuterium oxide. The IUPAC name is (2H₂)water. It belongs to product categories of Inorganics; Heavy Water (Deuterium Oxide); Alphabetical Listings; D; Stable Isotopes. Its EINECS registry number is 232-148-9. In addition, the formula is D₂O and the molecular weight is 20.03. The chemical is a colourless liquid and should be stored in sealed containers in cool, dry place. What's more, it is obtained by liquid hydrogen distillation. During using it, avoid contact with skin and eyes.

Physical properties about Heavy water are: (1)ACD/BCF (pH 5.5): 1; (2)ACD/BCF (pH 7.4): 1; (3)#H bond acceptors: 1; (4)#H bond donors: 2; (5)Index of Refraction: 1.329; (6)Molar Refractivity: 3.676 cm³; (7)Molar Volume: 18.045 cm³; (8)Polarizability: 1.457×10^-24cm³; (9)Surface Tension: 72.269 dyne/cm; (10)Density: 1.11 g/cm³; (11)Enthalpy of Vaporization: 40.65 kJ/mol; (12)Boiling Point: 100 °C at 760 mmHg; (13)Vapour Pressure: 24.475 mmHg at 25 °C.

Uses of Heavy water: it is used in nuclear magnetic resonance spectroscopy when the solvent of interest is water and the nuclide of interest is hydrogen. It is often used as the source of deuterium for preparing specifically labelled isotopologs of organic compounds and used instead of water when collecting FTIR spectra of proteins in solution. What's more, it is used in certain types of nuclear reactors where it acts as a neutron moderator to slow down neutrons.

You can still convert the following datas into molecular structure:
1. SMILES: [2H]O[2H]
2. InChI: InChI=1/H2O/h1H2/i/hD2
3. InChIKey: XLYOFNOQVPJJNP-ZSJDYOACEI
4. Std. InChI: InChI=1S/H2O/h1H2/i/hD2
5. Std. InChIKey: XLYOFNOQVPJJNP-ZSJDYOACSA-N