| Full text | |
| Author(s): |
Total Authors: 2
|
| Affiliation: | [1] Univ Fed Sao Carlos, Dept Fis, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083859 Campinas, SP - Brazil
Total Affiliations: 2
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| Document type: | Journal article |
| Source: | Physical Chemistry Chemical Physics; v. 17, n. 38, p. 24716-24721, 2015. |
| Web of Science Citations: | 7 |
| Abstract | |
We discuss the role of nuclear quantum fluctuations in ice I-h, focusing on the hydrogen-bond (HB) structure and the molecular dipole-moment distribution. For this purpose we carry out DFT-based first-principles molecular dynamics and path-integral molecular dynamics simulations at T = 100 K. We analyze the HB structure in terms of a set of parameters previously employed to characterize molecular structures in the liquid phase and compute the molecular dipole moments using the maximally-localized Wannier functions. The results show that the protons experience very large digressions driven by quantum fluctuations, accompanied by major rearrangements in the electronic density. As a result of these protonic quantum fluctuations the molecular dipole-moment distribution is substantially broadened as well as shifted to a larger mean value when compared to the results obtained when such fluctuations are neglected. In terms of dielectric constants, the reconciliation between the greater mean dipole moment and experimental indications that the dielectric constant of H2O ice is lower than that of D2O ice would indicate that the topology of the HB network is sensitive to protonic quantum fluctuations. (AU) | |
| FAPESP's process: | 13/08293-7 - CCES - Center for Computational Engineering and Sciences |
| Grantee: | Munir Salomao Skaf |
| Support Opportunities: | Research Grants - Research, Innovation and Dissemination Centers - RIDC |