Related papers: A computed line list for the H2D+ molecular ion
The proton, deuteron and triton masses can be determined relative to the electron mass via rovibrational spectroscopy of molecular hydrogen ions. This has to occur via comparison of the experimentally measured transition frequencies and the…
The precise measurement of transition frequencies in cold, trapped molecules has applications in fundamental physics, and extremely high accuracies are desirable. We determine suitable candidates by considering simple molecules with a…
The systematic shifts of the transition frequencies in the molecular hydrogen ions are of relevance to ultra-high-resolution radio-frequency, microwave and optical spectroscopy of these systems, performed in ion traps. We develop the…
We use optical frequency comb Fourier transform spectroscopy to record high-resolution, low-pressure, room-temperature spectra of formaldehyde (H$_2$$^{12}$C$^{16}$O) in the range of 1250 to 1390 cm$^{-1}$. Through line-by-line fitting, we…
Protonated molecular species have been proven to be abundant in the interstellar gas. This class of molecules is also pivotal for the determination of important physical parameters for the ISM evolution (e.g. gas ionisation fraction) or as…
Optimal set of 1050 rovibronic energy levels for 35 triplet electronic states of $D_2$ has been obtained by means of a statistical analysis of all available wavenumbers of triplet-triplet rovibronic transitions studied in emission,…
CH2D+, the singly deuterated counterpart of CH3+, offers an alternative way to mediate formation of deuterated species at temperatures of several tens of K, as compared to the release of deuterated species from grains. We report a…
Aims. We study whether rotational excitation makes a difference to the abundances of the $\rm H_3^+$ isotopologs, including spin states, in physical conditions corresponding to starless cores and protostellar envelopes. Methods. We…
The fundamental vibrational interval of H$_{2}^+$ has been determined to be $\Delta G _{1/2} = 2191.126\,614(17)$ cm$^{-1}$ by continuous-wave laser spectroscopy of Stark manifolds of Rydberg states of H$_2$ with the H$_{2}^+$ ion core in…
Thioformaldehyde is an abundant molecule in various regions of the interstellar medium. However, available laboratory data limit the accuracies of calculated transition frequencies in the submillimeter region, in particular for minor…
HOCO$^+$ is a polar molecule that represents a useful proxy for its parent molecule CO$_2$, which is not directly observable in the cold interstellar medium. This cation has been detected towards several lines of sight, including massive…
Recently a high precision spectroscopic investigation of the EF^1\Sigma_g^+ - X^1\Sigma_g^+ system of molecular hydrogen was reported yielding information on QED and relativistic effects in a sequence of rotational quantum states in the…
In the interstellar cold gas, the chemistry of formaldehyde (H$_2$CO) can be essential to explain the formation of complex organic molecules. On this matter, the massive and energetic protostellar object G331 is still unexplored and, hence,…
We describe the current status of high-precision ab initio calculations of the spectra of molecular hydrogen ions (H_2^+ and HD^+) and of two experiments for vibrational spectroscopy. The perspectives for a comparison between theory and…
An optimal set of 1050 rovibronic energy levels for 35 triplet electronic states of $D_2$ has been obtained by means of a statistical analysis of all available wavenumbers of triplet-triplet rovibronic transitions studied in emission,…
An analysis of the measured rovibrational transitions is carried out for the 12C32S2 isotopologue of carbon disulfide. Data from 21 sources is extracted and validated using a consistent set of standard linear molecule quantum numbers. A…
We carried out a millimeter wavelength line survey between 79 and 356 GHz with the IRAM-30m telescope to investigate the physical and chemical properties of the molecular envelope of the oxygen-rich AGB star IK Tau. We analysed the…
Predicting solid-solid phase transitions remains a long-standing challenge in materials science. Solid-solid transformations underpin a wide range of functional properties critical to energy conversion, information storage, and thermal…
A prerequisite for laser cooling a molecular anion, which has not been achieved so far, is the precise knowledge of the relevant transition frequencies in the cooling scheme. To determine these frequencies we present a versatile method that…
Astronomical observations of (sub)millimeter wavelength pure rotational emission lines of the second most abundant molecule in the Universe, CO, hold the promise of probing regions of high temperature and density in the innermost parts of…