Polarization and Experimental Configuration Analysis of Sum Frequency Generation Vibrational Spectra of Air/Water Interface

Details Polarization and Experimental Configuration Analysis of Sum Frequency Generation Vibrational Spectra of Air/Water Interface Polarization and Experimental Configuration Analysis of Sum Frequency Generation Vibrational Spectra of Air/Water Interface

2005-08-24

arxiv.org/abs/cond-mat/0508568v1

J. Chem. Phys., 124, 114705(15 pages),2006

Physics

Condensed Matter

Other Condensed Matter

Scientific paper

10.1063/1.2179794

Here we report a detailed study on spectroscopy, structure and dynamics of water molecules at air/water interface, investigated with Sum Frequency Generation Vibrational Spectroscopy (SFG-VS). Quantitative polarization and experimental configuration analysis of the SFG data in different polarizations with four sets of experimental configurations can shed new lights on our present understanding of the air/water interface. Firstly, we concluded that the motion of the interfacial water molecules can only be in a limited angular range, instead rapidly varying over a broad angular range in the vibrational relaxation time suggested previously. Secondly, because different vibrational modes of different molecular species at the interface has different symmetry properties, polarization and symmetry analysis of the SFG-VS spectral features can help assignment of the SFG-VS spectra peaks to different interfacial species. These analysis concluded that the narrow 3693cm-1 and broad 3550cm-1 peaks belong to C_ v symmetry, while the broad 3250cm-1 and 3450cm-1 peaks belong to the symmetric stretching modes with C_2v symmetry. Thus, the 3693cm-1 peak is assigned to the free OH, the 3550cm-1 peak is assigned to the single hydrogen bonded OH stretching mode, and the 3250cm-1 and 3450cm-1 peaks are assigned to interfacial water molecules as two hydrogen donors for hydrogen bonding (with C_2v symmetry), respectively. Thirdly, analysis of the SFG-VS spectra concluded that the singly hydrogen bonded water molecules at the air/water interface have their dipole vector direct almost parallel to the interface, and is with a very narrow orientational distribution. The doubly hydrogen bond donor water molecules have their dipole vector point away from the liquid phase.

Affiliated with

Also associated with

No associations

Rating

Polarization and Experimental Configuration Analysis of Sum Frequency Generation Vibrational Spectra of Air/Water Interface does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Polarization and Experimental Configuration Analysis of Sum Frequency Generation Vibrational Spectra of Air/Water Interface, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polarization and Experimental Configuration Analysis of Sum Frequency Generation Vibrational Spectra of Air/Water Interface will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-268532