Towards understanding the astrochemistry of metal-compounds: Laboratory characterization of aluminum-bearing species through rotational spectroscopy and coupled-cluster calculations

星际尘埃由分子前体形成，在星星形成过程中以及伴随的与星际介质的相互作用中起着重要作用。从高分辨率的旋转光谱中，可以识别晚型恒星尘埃粒子的分子种子，因为它们的光谱特征是从实验室研究中得知的。最近的一个例子是在巨大的YV CMa的外壳中检测到TiO 2。射电天文观测的另一个重要方面是确定恒星核合成过程中形成的元素的同位素丰度，这可以通过实验室光谱学来识别。这两个中心问题将通过实验和量子化学相结合的方法来解决。拟议的研究包括对小金属轴承分子，特别是铝和钛化合物的光谱研究，这些分子将在超音速射流中产生。通过高分辨率光谱学，将获得精确的吸收频率，这将作为未来天体物理观测的基本前提。实验将得到高水平的最先进的量子化学计算的支持。

The formation of interstellar dust from molecular precursors plays an important role in the process of star formation and the accompanying interplay with the interstellar medium. From high resolution rotational spectra the molecular seeds of dust particles of late type stars can be identified, given that their spectral signatures are known from laboratory investigations. A recent example is the detection of TiO2 in the shell of giant YV CMa. Another important aspect of radio-astronomical observations is the determination of isotopic abundances form elements formed in the stellar nuclear-synthesis, which can be identified by means of laboratory spectroscopy.These two central questions will be addressed by a combined experimental and quantum chemical approach. The proposed research comprises spectroscopic investigations on small metal-bearing molecules, particularly aluminum- and titanium compounds, which will be produced in a supersonic jet. By means of high resolution spectroscopy precise absorption frequencies will be obtained, which will serve future astrophysical observations as fundamental prerequisite. The experiments will be supported by high level state-of-the-art quantum-chemical calculations.