An investigation of electron helicity density in bromocamphor and dibromocamphor as a source of electron circular dichroism
An investigation of electron helicity density in bromocamphor and dibromocamphor as a source of electron circular dichroism
复制标题
作为电子圆二色性来源的溴樟脑和二溴樟脑中电子螺旋密度的研究
DOI：
10.1088/0953-4075/39/9/006
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
T. Gay
中科院分区：
文献类型：
--
作者：
A. Scheer;G. Gallup;T. Gay
我们研究了溴樟脑和二溴樟脑的电子-圆二色谱(ECD)的原因，特别是目标的电子螺旋度密度。利用电子透射谱(ETS)和量子化学计算，对溴樟脑和二溴樟脑的暂时负离子状态进行了观察和归属。进一步计算确定了这些化合物的螺旋度密度。在通常未被占据的分子轨道的波函数幅值较大的区域发现了较大的螺旋度密度，这是造成散射截面共振的原因。我们将我们的ETS指认和螺旋度密度结果与Münster小组(Nolting等1997 J.Phys)在电子-圆二向色性实验中观察到的手性不对称数据联系起来。B：在。摩尔。选择。太棒了。305491)。我们的结果支持螺旋度密度可能是溴樟脑和二溴樟脑在某些共振位置手性不对称性的来源。
We investigate the causes of electron-circular dichroism (ECD) in bromocamphor and dibromocamphor, focusing specifically on the electron helicity density of the target. Using electron transmission spectroscopy (ETS) and quantum chemical calculations, we have observed and assigned temporary negative ion states of bromocamphor and dibromocamphor. Further calculations were conducted to determine the helicity densities of these compounds. Large helicity densities are found in the regions of large wavefunction amplitude of the normally unoccupied molecular orbitals responsible for resonances in the scattering cross sections. We relate our ETS assignments and helicity density results to the chiral asymmetry data observed in electron-circular dichroism experiments by the Münster group (Nolting et al 1997 J. Phys. B: At. Mol. Opt. Phys. 30 5491). Our results support helicity density as a possible source of chiral asymmetry at certain resonance positions in bromocamphor and dibromocamphor.