The T, /7-Dependence of the Chemical Shift of the Hydroxyl Protons in Deeply Supercooled Methanol and Water
نویسندگان
چکیده
The hydroxyl proton chemical shifts 6 ( H O ) of supercooled methanol (7"min= 149 K) and water have been determined (7"min= 183 K), and the pressure dependence of these shifts was measured up to 200 MPa. In both compounds the downfield shift of <5 ( H O ) continues down to the lowest temperatures reached. This result disagrees with the two state models for the hydrogen bond formation in both liquids. The isotherms ö (H 2 0 ) show for T< 273 K an upfield shift that becomes more pronounced with decreasing temperature. For 6 ( H O C H ^ ) , increas ingp causes at all temperatures a downshif t .
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