This chemical is called Nickelous difluoride tetrahydrate, and its CAS registry number is 13940-83-5. With the molecular formula of F₂H₈NiO₄, its molecular weight is 168.75. In addition, this chemical should be sealed in the ventilated and dry place, away from acid. It's used on fluorinating agent and the synthesis on xenon hexafluoride.

Other characteristics of the Nickelous difluoride tetrahydrate can be summarised as followings: (1)H-Bond Donor: 4; (2)H-Bond Acceptor: 6; (3)Rotatable Bond Count: 0; (4)Exact Mass: 167.974413; (5)MonoIsotopic Mass: 167.974413; (6)Topological Polar Surface Area: 4; (7)Heavy Atom Count: 7; (8)Formal Charge: 0; (9)Complexity: 2.8; (10)Isotope Atom Count: 0; (11)Covalently-Bonded Unit Count: 5; (12)Polar Surface Area: 36.92 Å².

When you are using this chemical, please be cautious about it as the following: This chemical is toxic and irritating to eyes, respiratory system and skin. Do not breathe dust. You should wear suitable protective clothing if you use it. In case of contacting with eyes, rinse immediately with plenty of water and seek medical advice. 

You can still convert the following datas into molecular structure:
1.SMILES: [Ni+2].[F-].[F-].O.O.O.O
2.InChI: InChI=1/2FH.Ni.4H2O/h2*1H;;4*1H2/q;;+2;;;;/p-2
3.InChIKey: HHPKUIWWHLVHQQ-NUQVWONBAU