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Updated: Jan 1, 2026

Harmonic Nanoparticles for Regenerative Research
Published on: May 1, 2014
NaRb3B6O9(OH)3(HCO3): A Borate-Bicarbonate Nonlinear Optical Material
Fenghua Ding1, Weilong Zhang2, Matthew L Nisbet1
1Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.
Abstract:
A noncentrosymmetric mixed alkali metal borate-bicarbonate, NaRb3B6O9(OH)3(HCO3), was synthesized and characterized. The compound crystallizes in the monoclinic space group P21 (No. 4) with a = 8.988(3) Å, b = 8.889(2) Å, c = 10.068(4) Å, and β = 114.6(4)°. The structure features a combination of chains of boron-oxygen [B6O9 (OH)3]3- groups and isolated HCO3- groups, with charge compensation provided by Rb+ and Na+ cations. It exhibits a second harmonic generation response of about 0.5 × KDP. The UV-vis-NIR absorption spectrum indicated a transparency of about 40% at 200 nm. The IR spectrum confirms the coordination environments of anionic groups, and thermogravimetric measurements indicate the material is thermally stable up to approximately 320 °C. Additionally, first-principles calculations were performed in order to gain insight into the role of boron-oxygen and HCO3- groups with respect to the band structure and NLO properties.
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