Journal
JOURNAL OF PHYSICAL CHEMISTRY C
Volume 120, Issue 17, Pages 9357-9363Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.jpcc.6b03275
Keywords
-
Funding
- Ministry of Education, Culture Sports, Science and Technology (MEXT) [25104005, 25288014]
- Grants-in-Aid for Scientific Research [25104005, 25288014] Funding Source: KAKEN
Ask authors/readers for more resources
Complex chi((2)) spectra of buried silica/isotopically diluted water (HOD-D2O) interfaces were measured using multiplex heterodyne-detected vibrational sum frequency generation spectroscopy to elucidate the hydrogen bond structure and up/down orientation of water at the silica/water interface at different pHs. The data show that-vibrational coupling (inter- and/or intrarnolecular coupling) plays a significant role in determining the chi((2)) spectral feature of silica/H2O interfaces and indicate that the doublet feature in the H2O spectra does not represent two distinct water structures (i.e., the ice and liquid-like structures) at the silica/water interface. The observed pH dependence of the imaginary chi((2)) spectra is explained by (1) H-up oriented water donating a hydrogen bond to the oxygen atom of silanolate, which is accompanied by H-up water oriented by the electric field created by the negative charge of silanolate, (2) H-up oriented water which donates a hydrogen bond to the neutral silanol oxygen, and (3) H-down oriented water which accepts hydrogen bonds from the neutral silanol and donates hydrogen bonds to bulk water molecules. The broad continuum of the OH stretch band of HOD-D2O and a long tail in the low frequency region represent a wide distribution of strong hydrogen bonds at the silica/water interface, particularly at the low pH.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available