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The similar slopes the potential energy curves generated the

(洛阳师范学院化学化工学院, 河南 洛阳 471022)

摘要: X―H···Y (Y为电子供体)型氢键形成时, X―H键长伸长或缩短与相应的X―H伸缩振动频率红移或蓝 移存在较强的相关性, 这也是氢键光谱检测和研究的基础. 但是, 最近的理论研究却推翻了这一观点, 认为X―

ZHANG Yu MA Ning

Abstract: The correlation between the X―H bond-length change and the corresponding X―H stretching frequency shift upon X ― H···Y (Y is an electron donor) hydrogen bond formation is the basis for the spectroscopic detection and investigation of the hydrogen bond. However, this view has been questioned in a recent report, suggesting that the widely accepted correlation between the bond-length change and the frequency shift in hydrogen-bonded complexes is unreliable (McDowell, S. A. C.; Buckingham, A. D. J. Am. Chem. Soc. 2005, 127, 15515.). In this work, several robust computational methods have been used to investigate this issue. The results clearly show that a computational artifact leads to the conclusion incorrectly reported by McDowell and Buckingham and that the correlation between the X―H bond-length change and the corresponding X―H stretching frequency shift is still very good in the hydrogen-bonded complexes studied.

frared and Raman spectroscopies have played important roles in the detection of the hydrogen bonds: conventional X―H···

Received: November 4, 2011; Revised: December 27, 2011; Published on Web: December 30, 2011.

Ⓒ Editorial office of Acta Physico⁃Chimica Sinica

Fig.1 Linear complexes considered in this work The red dot lines represent the hydrogen bonds.

Fig.2

Potential energy curves for the linear complex ClH···O≡C at different levels of theory
All results reflect counterpoise correction.

QCISD/6-311++G(2d,2p) and QCISD/6-311++G(3df,3pd) lev-els of theory are inaccurate relative to the CCSD(T)/CBS benchmark, and furthermore they can not produce the correct results of the bond-length change and the frequency shift. Let us add here that McDowell and Buckinghamʹs conclusions are based on the QCISD/6-311 ++ G(2d,2p) and QCISD/6-311 ++ G(3df,3pd) calculations. 5 In comparison with the CCSD(T)/ CBS benchmark, the similar slopes of the potential energy curves generated at the M05-2X/6-311 ++ G(3d,3p), M06-2X/ 6-311++G(3d,3p), B2PLYP-D/6-311++G(3d,3p), and mPW2PL-YP-D/6-311++G(3d,3p) levels of theory confirm the reliability of the density functionals M05-2X, M06-2X, B2PLYP-D, and mPW2PLYP-D for the study of the bond-length change-fre-quency shift correlation of the hydrogen-bonded complexes considered in the present study.

The highly accurate CCSD(T)/CBS potential energy curve was

3.2
0.12744 0.12772 0.12855 0.12736 0.12749 0.12755
0.23720 0.24164 0.23663 0.23917 0.24346 0.22376
3004.7 2956.1 2817.8 3013.2 2997.1 2994.9

I(Cl―H)

144 244 549 113 163 197
μ 4.6942×10-30 5.3284×10-30 9.3925×10-30 1.5674×10-30 4.8247×10-30 5.4885×10-30
ΔE CP 3.85 6.82 13.85 1.21 4.10 6.99

6-311++G(3df,3pd)

502 Acta Phys.Chim. Sin. 2012 Vol.28

Fig.3 Correlation of ClH bond-length change with ClH stretching frequency shift in hydrogen-bonded complexes

503
S.; Alkorta, I.; Clary, D. C.; Crabtree, R. H.; Dannenberg, J. J.;
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