The Calcium sulfate hemihydrate with CAS registry number of 10034-76-1 is also known as Sulfuric acid, calciumsalt, hydrate (2:2:1). The IUPAC name is Dicalcium disulfate hydrate. It belongs to product categories of Inorganic Salts; Synthetic Reagents. Its EINECS registry number is 231-900-3. In addition, the formula is Ca.H₂O₄S.1/2H₂O and the molecular weight is 147.15. This chemical is a white or slightly off-white powder or granules that soluble in acid, ammonium salt, sodium thiosulfate and glycerol. It can be used in building board, agriculture and also can be used as tablet, diluent, filler, curing agent and so on. During using it, do not breathe dust and avoid contact with skin and eyes.

Physical properties about Calcium sulfate hemihydrate are: (1)ACD/LogP: -1.03; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): -5.53; (4)ACD/LogD (pH 7.4): -5.53; (5)ACD/BCF (pH 5.5): 1; (6)ACD/BCF (pH 7.4): 1; (7)#H bond acceptors: 4; (8)#H bond donors: 2; (9)Polar Surface Area: 82.98Ų; (10)Enthalpy of Vaporization: 62.94 kJ/mol; (11)Boiling Point: 330 °C at 760 mmHg; (12)Vapour Pressure: 3.35E-05 mmHg at 25 °C.

Preparation of Calcium sulfate hemihydrate: it is prepared by rotary kiln calcination. Gypsum is crushed to l~3 mm, added to heated rotary kiln and heated for 15 minutes. Finally, product is obtained by screening crushed clinker. Meanwhile, αCaSO4·0.5H2O is prepared by pressure method. Gypsum is crushed into 15 ~ 20 mm and added to autoclave. Then it is cooked for 7 hours in certain pressure at the temperature of 120 °C. At last, the reactor is dryed at 120-220 °C, crushed and sieved to obtain product.

CaSO₄·2H₂O → β CaSO4·0.5H₂O + 1.5 H₂O
CaSO₄·2H₂O → α CaSO4·0.5H₂O + 1.5 H₂O

You can still convert the following datas into molecular structure:
1. Canonical SMILES: O.[O-]S(=O)(=O)[O-].[O-]S(=O)(=O)[O-].[Ca+2].[Ca+2]
2. InChI: InChI=1S/2Ca.2H2O4S.H2O/c;;2*1-5(2,3)4;/h;;2*(H2,1,2,3,4);1H2/q2*+2;;;/p-4
3. InChIKey: ZOMBKNNSYQHRCA-UHFFFAOYSA-J