Methylphosphonyl difluoride (DF), also called methyl difluorophosphite, methylphosphonic difluoride, and difluoromethylphosphine oxide, is a chemical weapon precursor. Its chemical formula is CH3POF2. It is a Schedule 1 substance in the sense of the Chemical Weapons Convention. It is used for production of sarin and soman as a component of binary chemical weapons; an example is the M687 artillery shell, where it is used together with a mixture of isopropyl alcohol and isopropyl amine, producing sarin.

CAS：676-99-3
中文别名：
英文别名：Methylphosphonic difluoride;methylphosphonicdifluorid;methylphosphonic difluoride;Phosphonodifluoridic acid,methyl;Phosphonic difluoride,methyl;Methyl-phosphonsaeure-difluorid;Difluoromethylphosphine oxide;methylphosphonic acid difluoride;Difluoro;Methylphosphonyl difluoride;Methyl difluorophosphite;methylphosphonodifluoridate;
分子式：CH3F2OP
分子量：100.004
精确质量：99.989
Psa：26.88
Logp：1.7483

密度：1.384 g/cm3
沸点：98-99ºC
熔点：-37ºC
折射率：1.276
储存条件：库房低温,通风,干燥,与食品原料分开存放

危险类别码：R34; R36/37/38
危险品运输编码：UN 3265