The Calculation of Pressure-Induced Shifts and Pressure- Broadening Coefficients for H20 and Other Important Atmospheric Asymmetric Rotor Molecules

小行星9415454 本项目将侧重于开发一个理论框架，以计算大气中重要物种的压力加宽半宽度（）和压力诱导谱线偏移（）。 半宽度是遥感数据和用于计算温室气体辐射强迫的逐线模型中误差的主要来源。 为了解决这些问题，需要数千个旋转振动跃迁的数据。 因此，需要一个理论模型，计算效率高，能够实现5%的不确定性。 Baranger、Kolb和Greim（BKG）的预解算子形式主义是理论方法的基础。 计算将使用真实的分子动力学、显式速度平均以及相互作用势中的所有相关项。 计算将对大气中重要的转子分子（H2O，O3，SO2，NO2，H2S）进行N2或O2和自相互作用的扰动。 有许多实验测量与理论进行比较和测试。 一旦理论问题得到解决， 和 对于每一种物质都将产生大气中重要的跃迁。 的振动，转动状态，和温度依赖的半宽度和线位移将被调查。 这项工作的主要目标是提高我们对遥感结果的信心，并更好地确定温室气体的辐射强迫。

9415454 Gamache This project will focus on the development of a theoretical framework to calculate pressure-broadened halfwidths ( ) and pressure-induced line shifts ( ) for atmospherically important species. The halfwidth is the major source of error in remote sensing data and in line-by-line models used to calculate radiative forcing from greenhouse gases. To address these problems, data are needed for thousands of rotational-vibrational transitions. Hence a theoretical model is needed that is computationally efficient and capable of achieving 5% uncertainty in . The resolvent operator formalism of Baranger, Kolb, and Greim (BKG) is the basis of the theoretical approach. Calculations will use realistic molecular dynamics, explicit velocity averaging, and all relevant terms in the interaction potential. Calculations will be done for atmospherically important rotor molecules (H2O, O3, SO2, NO2, H2S) perturbed by N2 or O2 and self-interactions. There are a number of experimental measurements to compare with and test the theory. Once the theoretical questions are resolved, a database of and for atmospherically important transitions will be generated for each species. The vibrational, rotational state, and temperature dependence of the halfwidths and line-shifts will be investigated. The major objective of this work is to improve our confidence in remote sensing results and allow a better determination of the radiative forcing of greenhouse gases.