The Pressure Broadening of Spectral Lines
The Pressure Broadening of Spectral Lines
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谱线的压力展宽
DOI：
10.1103/physrev.69.616
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发表时间：
1946
期刊：
影响因子：
--
通讯作者：
H. Foley
中科院分区：
文献类型：
--
作者：
H. Foley
从绝热碰撞近似下的量子辐射理论出发，导出了压宽线中光强分布的傅里叶积分表达式。在考虑了实际相移分布的情况下，得到了解的相移近似。结果表明，一般情况下，随着压力的增大，谱线位置会发生位移，谱线也会变宽。位移与展宽的比率只取决于分子间距离的幂，分子间的相互作用随着分子间距离的减小而减小。在国外气体展宽中，这一比值的实验值与反六次方平均一致。预测的线宽略大于Weisskopf给出的线宽。大多数碱金属吸收谱线与观察到的谱线宽度符合得很好。给出了线性极性分子振动-旋转线的计算线宽和位移。给出了一种处理非绝热碰撞的方法。给出了洛伦兹线型向Margenau型线型转化的条件。结果表明，在适当的物理条件下，平动运动的Jablonski波力学处理方法与傅立叶积分方法得到了相同的线形。
The Fourier integral expression for the intensity distribution in a pressure broadened line is derived from the quantum radiation theory with an adiabatic collision approximation. The phase shift approximation to the solution is obtained with the actual distribution of phase shifts taken into account. It is shown that in general there is a shift in line position as well as a line broadening both proportional to the pressure. The ratio of the shift to the broadening depends only on the power of the intermolecular distance with which the interaction decreases. Experimental values of this ratio in foreign gas broadening are on the average consistent with the inverse sixth power. The predicted line widths are slightly larger than those given by Weisskopf. Good agreement with the observed line width is found for most of the alkali metals absorption lines. Calculated line widths and shifts are given for the vibration-rotation lines of linear polar molecules. A method for treating non-adiabatic collisions is given. The conditions for which the Lorentz line form transforms to the Margenau-type line form are indicated. It is shown that the Jablonski wave mechanical treatment of translational motion leads to the same line forms as the Fourier integral method under the proper physical conditions.