The 1,9-Nonanedithiol, with the CAS registry number 3489-28-9 and EINECS registry number 222-482-3, has the systematic name of nonane-1,9-dithiol. It is a kind of air sensitive chemical, and the molecular formula of the chemical is C₉H₂₀S₂.

The characteristics of this chemical are as followings: (1)ACD/LogP: 4.40; (2)# of Rule of 5 Violations: 0; (3)#H bond acceptors: 0; (4)#H bond donors: 0; (5)#Freely Rotating Bonds: 10; (6)Polar Surface Area: 50.6 Å²; (7)Index of Refraction: 1.492; (8)Molar Refractivity: 59.53 cm³; (9)Molar Volume: 205.1 cm³; (10)Polarizability: 23.6×10^-24cm³; (11)Surface Tension: 33.5 dyne/cm; (12)Density: 0.937 g/cm³; (13)Flash Point: 101.7 °C; (14)Enthalpy of Vaporization: 49.72 kJ/mol; (15)Boiling Point: 279.4 °C at 760 mmHg; (16)Vapour Pressure: 0.00684 mmHg at 25°C.

Uses of 1,9-Nonanedithiol: It can react with 4,4'-Bis-brommethyl-benzophenon to produce 2,12-Dithia[1.13]paracyclophan-20-on. This reaction will need reagent Cs₂CO₃, and the menstruum toluene and ethanol. The reaction time is 44 hour with heating, and the yield  is about 75%.  

You should be cautious while dealing with this chemical. It irritates to eyes, respiratory system and skin and harmful if swallowed. Therefore, you had better take the following instructions: Wear suitable protective gloves and eye/face protection, and if in case of contacting with eyes, rinse immediately with plenty of water and seek medical advice.

Addtionally, the following datas could be converted into the molecular structure:
(1)SMILES: SCCCCCCCCCS
(2)InChI: InChI=1/C9H20S2/c10-8-6-4-2-1-3-5-7-9-11/h10-11H,1-9H2
(3)InChIKey: GJRCLMJHPWCJEI-UHFFFAOYAO