Gradual crossover in molecular organization of stable liquid H2O at moderately high pressure and temperature

Yoshikata Koga, Peter Westh, Koh Yoshida, Akira Inaba, Yasuhiro Nakazawa

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

    Resumé

    Using the literature raw data of the speed of sound and the specific volume, the isothermal compressibility, κ T , a second derivative thermodynamic quantity of G, was evaluated for liquid H2O in the pressure range up to 350 MPa and the temperature to 50 ºC. We then obtained its pressure derivative, dκ T /dp, a third derivative numerically without using a fitting function to the κ T data. On taking yet another p-derivative at a fixed T graphically without resorting to any fitting function, the resulting d2 κ T /dp 2, a fourth derivative, showed a weak but clear step anomaly, with the onset of the step named point X and its end point Y. In analogy with another third and fourth derivative pair in binary aqueous solutions of glycerol, dα p /dx Gly and d2 α p /dx Gly 2, at 0.1 MPa (α p is the thermal expansivity and x Gly the mole fraction of solute glycerol) in our recent publication [J. Solution Chem. 43, 663-674 (2014); DOI:10.1007/s10953-013-0122-7], we argue that there is a gradual crossover in the molecular organization of pure H2O from a low to a high p-regions starting at point X and ending at Y at a fixed T. The crossover takes place gradually spanning for about 100 MPa at a fixed temperature. The extrapolated temperature to zero p seems to be about 70 – 80 °C for points X and 90 – 110 °C for Y. Furthermore, the mid-points of X and Y seem to extrapolate to the triple point of liquid, ice Ih and ice III. Recalling that the zero x Gly extrapolation of point X and Y for binary aqueous glycerol at 0.1 MPa gives about the same T values respectively, we suggest that at zero pressure the region below about 70 °C the hydrogen bond network is bond-percolated, while above about 90 ºC there is no hydrogen bond network. Implication of these findings is discussed
    OriginalsprogDansk
    Artikelnummer097116
    TidsskriftA I P Advances
    Vol/bind4
    ISSN2158-3226
    DOI
    StatusUdgivet - 2014

    Citer dette

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    title = "Gradual crossover in molecular organization of stable liquid H2O at moderately high pressure and temperature",
    abstract = "Using the literature raw data of the speed of sound and the specific volume, the isothermal compressibility, κ T , a second derivative thermodynamic quantity of G, was evaluated for liquid H2O in the pressure range up to 350 MPa and the temperature to 50 ºC. We then obtained its pressure derivative, dκ T /dp, a third derivative numerically without using a fitting function to the κ T data. On taking yet another p-derivative at a fixed T graphically without resorting to any fitting function, the resulting d2 κ T /dp 2, a fourth derivative, showed a weak but clear step anomaly, with the onset of the step named point X and its end point Y. In analogy with another third and fourth derivative pair in binary aqueous solutions of glycerol, dα p /dx Gly and d2 α p /dx Gly 2, at 0.1 MPa (α p is the thermal expansivity and x Gly the mole fraction of solute glycerol) in our recent publication [J. Solution Chem. 43, 663-674 (2014); DOI:10.1007/s10953-013-0122-7], we argue that there is a gradual crossover in the molecular organization of pure H2O from a low to a high p-regions starting at point X and ending at Y at a fixed T. The crossover takes place gradually spanning for about 100 MPa at a fixed temperature. The extrapolated temperature to zero p seems to be about 70 – 80 °C for points X and 90 – 110 °C for Y. Furthermore, the mid-points of X and Y seem to extrapolate to the triple point of liquid, ice Ih and ice III. Recalling that the zero x Gly extrapolation of point X and Y for binary aqueous glycerol at 0.1 MPa gives about the same T values respectively, we suggest that at zero pressure the region below about 70 °C the hydrogen bond network is bond-percolated, while above about 90 ºC there is no hydrogen bond network. Implication of these findings is discussed",
    author = "Yoshikata Koga and Peter Westh and Koh Yoshida and Akira Inaba and Yasuhiro Nakazawa",
    year = "2014",
    doi = "10.1063/1.4895536",
    language = "Dansk",
    volume = "4",
    journal = "A I P Advances",
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    Gradual crossover in molecular organization of stable liquid H2O at moderately high pressure and temperature. / Koga, Yoshikata; Westh, Peter; Yoshida, Koh; Inaba, Akira; Nakazawa, Yasuhiro.

    I: A I P Advances, Bind 4, 097116, 2014.

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

    TY - JOUR

    T1 - Gradual crossover in molecular organization of stable liquid H2O at moderately high pressure and temperature

    AU - Koga, Yoshikata

    AU - Westh, Peter

    AU - Yoshida, Koh

    AU - Inaba, Akira

    AU - Nakazawa, Yasuhiro

    PY - 2014

    Y1 - 2014

    N2 - Using the literature raw data of the speed of sound and the specific volume, the isothermal compressibility, κ T , a second derivative thermodynamic quantity of G, was evaluated for liquid H2O in the pressure range up to 350 MPa and the temperature to 50 ºC. We then obtained its pressure derivative, dκ T /dp, a third derivative numerically without using a fitting function to the κ T data. On taking yet another p-derivative at a fixed T graphically without resorting to any fitting function, the resulting d2 κ T /dp 2, a fourth derivative, showed a weak but clear step anomaly, with the onset of the step named point X and its end point Y. In analogy with another third and fourth derivative pair in binary aqueous solutions of glycerol, dα p /dx Gly and d2 α p /dx Gly 2, at 0.1 MPa (α p is the thermal expansivity and x Gly the mole fraction of solute glycerol) in our recent publication [J. Solution Chem. 43, 663-674 (2014); DOI:10.1007/s10953-013-0122-7], we argue that there is a gradual crossover in the molecular organization of pure H2O from a low to a high p-regions starting at point X and ending at Y at a fixed T. The crossover takes place gradually spanning for about 100 MPa at a fixed temperature. The extrapolated temperature to zero p seems to be about 70 – 80 °C for points X and 90 – 110 °C for Y. Furthermore, the mid-points of X and Y seem to extrapolate to the triple point of liquid, ice Ih and ice III. Recalling that the zero x Gly extrapolation of point X and Y for binary aqueous glycerol at 0.1 MPa gives about the same T values respectively, we suggest that at zero pressure the region below about 70 °C the hydrogen bond network is bond-percolated, while above about 90 ºC there is no hydrogen bond network. Implication of these findings is discussed

    AB - Using the literature raw data of the speed of sound and the specific volume, the isothermal compressibility, κ T , a second derivative thermodynamic quantity of G, was evaluated for liquid H2O in the pressure range up to 350 MPa and the temperature to 50 ºC. We then obtained its pressure derivative, dκ T /dp, a third derivative numerically without using a fitting function to the κ T data. On taking yet another p-derivative at a fixed T graphically without resorting to any fitting function, the resulting d2 κ T /dp 2, a fourth derivative, showed a weak but clear step anomaly, with the onset of the step named point X and its end point Y. In analogy with another third and fourth derivative pair in binary aqueous solutions of glycerol, dα p /dx Gly and d2 α p /dx Gly 2, at 0.1 MPa (α p is the thermal expansivity and x Gly the mole fraction of solute glycerol) in our recent publication [J. Solution Chem. 43, 663-674 (2014); DOI:10.1007/s10953-013-0122-7], we argue that there is a gradual crossover in the molecular organization of pure H2O from a low to a high p-regions starting at point X and ending at Y at a fixed T. The crossover takes place gradually spanning for about 100 MPa at a fixed temperature. The extrapolated temperature to zero p seems to be about 70 – 80 °C for points X and 90 – 110 °C for Y. Furthermore, the mid-points of X and Y seem to extrapolate to the triple point of liquid, ice Ih and ice III. Recalling that the zero x Gly extrapolation of point X and Y for binary aqueous glycerol at 0.1 MPa gives about the same T values respectively, we suggest that at zero pressure the region below about 70 °C the hydrogen bond network is bond-percolated, while above about 90 ºC there is no hydrogen bond network. Implication of these findings is discussed

    U2 - 10.1063/1.4895536

    DO - 10.1063/1.4895536

    M3 - Tidsskriftartikel

    VL - 4

    JO - A I P Advances

    JF - A I P Advances

    SN - 2158-3226

    M1 - 097116

    ER -