This chemical is called Ethylidenediphosphonic acid, and its CAS registry number is 6145-33-1. With the molecular formula of C₂H₈O₆P₂, its molecular weight is 190.03. 

Other characteristics of the Ethylidenediphosphonic acid can be summarised as followings: (1)ACD/LogP: -3.77; (2)# of Rule of 5 Violations: 0; (3)ACD/BCF (pH 5.5): 1; (4)ACD/BCF (pH 7.4): 1; (5)ACD/KOC (pH 5.5): 1; (6)ACD/KOC (pH 7.4): 1; (7)#H bond acceptors: 6; (8)#H bond donors: 4; (9)#Freely Rotating Bonds: 2; (10)Polar Surface Area: 90.68 Å²; (11)Index of Refraction: 1.534; (12)Molar Refractivity: 31.16 cm³; (13)Molar Volume: 100.2 cm³; (14)Polarizability: 12.35×10^-24cm³; (15)Surface Tension: 104.1 dyne/cm; (16)Density: 1.895 g/cm³; (17)Flash Point: 276.3 °C; (18)Enthalpy of Vaporization: 88.52 kJ/mol; (19)Boiling Point: 533.3 °C at 760 mmHg; (20)Vapour Pressure: 8.6E-13 mmHg at 25°C.

You can still convert the following datas into molecular structure:
1.SMILES: O=P(O)(O)C(C)P(=O)(O)O
2.InChI: InChI=1/C2H8O6P2/c1-2(9(3,4)5)10(6,7)8/h2H,1H3,(H2,3,4,5)(H2,6,7,8)
3.InChIKey: MXYOPVWZZKEAGX-UHFFFAOYAZ