[{"from": "human", "value": "Create a molecule that satisfies the conditions outlined in the description. The molecule is a dialkyl phosphate having ethyl as the alkyl group; major microspecies at pH 7.3 It is a conjugate base of a diethyl hydrogen phosphate."}, {"from": "gpt", "value": "[C][C][O][P][=Branch1][C][=O][Branch1][C][O-1][O][C][C]"}]