Dear Dr. Katouzian:

with a 100% surety all the IR peaks in your spectrum arise from water:

3321 - O-H stretching; 1636 H-O-H scissoring ; and a peak around 700-600 cm-1 which can not be seen in your spectrum should be ascribed as H-O-H out-of-plane deformation.

The above-said means that in order to see the peaks arising from the substance you have to increase the concentration of your solution at least 10-to-20 times.

of course you can demonstrate the complex formation

by ATR method but again you should use a very concentrated solution, or to dry the solution directly on ATR crystal

Good Luck,

Leonid

Dear Duyen Minh Pham:

The effects of the band-shifts for NH3+, -CO-NH- in presence of water indeed take place. BUT all these groups are absent in the FTIR spectrum of the substance shown in the attached file -- just because the spectrum clearly is the spectrum of water. The FTIR spectrum presented contains even a very low intensity broad peak at appr. 2100 cm-1 - should be attributed to water's combination band. There is no proof of presence of any other substance than water only.

Best Regards,

L. Vladimirov