Temperature dependence on the structure of Zundel cation and its isotopomers

Suzuki, Kimichi*; Tachikawa, Masanori*; Shiga, Motoyuki   

Temperature dependence on the structural fluctuations of Zundel cation, HO, and its isotopomers, DO and TO, have been studied using path integral molecular dynamics simulations in which nuclear quantum effect is fully taken into account. It has been found that the fluctuations of hydrogen-oxygen and oxygen-oxygen distances, which are relevant to the hydrogen bonded structure, grow drastically as the temperature increases within the range of investigation between 100 K and 900 K. The fluctuation with respect to the position of non-bonded hydrogen also increases substantially as the temperature increases. The temperature dependence on the fluctuation is greater for DO or TO than that of HO, since the zero-point effect of the former is less than the latter.