The Phosphonic acid,P-[(3-methylphenyl)methyl]-, with the CAS registry number 18945-65-8, is also known as 3-Methylbenzylphosphonic acid. This chemical's molecular formula is C₈H₁₁O₃P and molecular weight is 186.14. What's more, its systematic name is called (3-Methylbenzyl)phosphonic acid. When you are dealing with this chemical, you should be very careful. This chemical may destroy living tissue on contact. 

Physical properties about Phosphonic acid,P-[(3-methylphenyl)methyl]- are: (1) ACD/LogP: 0.22; (2) # of Rule of 5 Violations: 0; (3) ACD/LogD (pH 5.5): -2.87; (4) ACD/LogD (pH 7.4): -3.4; (5) ACD/BCF (pH 5.5): 1; (6) ACD/BCF (pH 7.4): 1; (7) ACD/KOC (pH 5.5): 1; (8) ACD/KOC (pH 7.4): 1; (9) #H bond acceptors: 3; (10) #H bond donors: 2; (11) #Freely Rotating Bonds: 2; (12) Polar Surface Area: 45.34 Å²; (13) Index of Refraction: 1.564; (14) Molar Refractivity: 45.93 cm³; (15) Molar Volume: 141.1 cm³; (16) Surface Tension: 56.6 dyne/cm; (17) Density: 1.318 g/cm³; (18) Flash Point: 187.3 °C; (19) Enthalpy of Vaporization: 66.97 kJ/mol; (20) Boiling Point: 386.1 °C at 760 mmHg; (21) Vapour Pressure: 1.19E-06 mmHg at 25 °C.

You can still convert the following datas into molecular structure:
(1) SMILES: O=P(O)(O)Cc1cccc(c1)C
(2) InChI: InChI=1/C8H11O3P/c1-7-3-2-4-8(5-7)6-12(9,10)11/h2-5H,6H2,1H3,(H2,9,10,11)
(3) InChIKey: YSZXYVIDVAUMLH-UHFFFAOYAE