Revisiting the integrated infrared intensities and atomic polar tensors of the boron trihalides

• Integrated fundamental intensities from PNNL spectra of BF3, BCl3 and BBr3 are reported.
• These results drastically modify a much older BCl3 stretching intensity value.
• Experimental and high level ab initio intensity results are now in excellent agreement.
• Revised experimental atomic polar tensors for BF3 and BCl3 are presented.
• Experimental atomic polar tensors for BBr3 are reported for the first time.

Integrated infrared intensities obtained from spectra of the Pacific Northwest National Laboratory (PNNL) database are reported for BF3, BCl3 and BBr3. The BF3 and BCl3 intensities are compared with values reported much earlier whereas the asymmetric BBr3 stretching intensity is reported for the first time. Although agreement is good for the BF3 intensities, the result from the PNNL spectra for the asymmetric BCl3 stretching vibration is about three times larger than the one reported earlier. The intensities obtained from the PNNL spectra are in excellent agreement with results from QCISD/cc–pVTZ quantum chemical calculations having an rms error of only 32.9 cm− 1 or 5.9% of the average intensity. Revised experimental atomic polar tensors and GAPT charges are reported for all these molecules.

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