Related papers: Rotational spectroscopy of isotopic oxirane, $c$-C…
We prepared a sample of oxirane doubly deuterated at one C atom and studied its rotational spectrum in the laboratory for the first time between 120~GHz and 1094~GHz. Accurate spectroscopic parameters up to eighth order were determined, and…
Cyclopropenone was first detected in the cold and less dense envelope of Sagittarius B2(N). It was found later in several cold dark clouds and it may be possible to detect its minor isotopic species in these environments. In addition, the…
We prepared a sample of mono-deuterated oxirane and studied its rotational spectrum in the laboratory between 490 GHz and 1060 GHz in order to improve its spectroscopic parameters and consequently the calculated rest frequencies of its…
Submillimeter spectra of three isotopomers of propyne containing one $^{13}$C atom were recorded in natural isotopic composition in the region of 426 GHz to 785 GHz. Additional measurements were carried out near 110 GHz. Combining these…
The rotational spectra of singly substituted $^{13}$C and $^{15}$N isotopic species of vinyl cyanide have been studied in natural abundances between 64 and 351 GHz. In combination with previous results, greatly improved spectroscopic…
We theoretically and numerically analyze x-ray scattering from asymmetric-top molecules three-dimensionally aligned using elliptically polarized laser light. A rigid-rotor model is assumed. The principal axes of the polarizability tensor…
The rotational spectrum of the formaldehyde isotopologue H$_2$C$^{17}$O was investigated between 0.56 and 1.50 THz using a sample of natural isotopic composition. In addition, transition frequencies were determined for H$_2$C$^{18}$O and…
A theoretical framework and computer code are developed for accurate calculations of coupled rotational-vibrational states in triatomic molecules using hyper-spherical coordinates and taking into account the Coriolis coupling effect.…
The rotational spectrum of silyl isocyanide (SiH$_3$NC), an isomer of the well studied silyl cyanide (SiH$_3$CN), has been detected in the laboratory in a supersonic molecular beam, and the identification was confirmed by observations of…
Methyl cyanide is an important trace molecule in space, especially in star-forming regions where it is one of the more common molecules used to derive kinetic temperatures. We want to obtain accurate spectroscopic parameters of minor…
In this paper we demonstrate how asymmetric molecular rotational spectra may be introduced to students both "pictorially" and with simple formulae. It is shown that the interpretation of such spectra relies heavily upon pattern recognition.…
A tunable far-infrared laser sideband spectrometer was used to investigate a nitric oxide sample enriched in 18O between 0.99 and 4.75 THz. Regular, electric dipole transitions were recorded between 0.99 and 2.52 THz, while magnetic dipole…
Ethyl cyanide is an abundant molecule in hot molecular clouds. Lines from 13C isotopically substituted ethyl cyanide were identified in Orion. To enable the search and the possible detection of other isotopologues of ethyl cyanide in…
Rotational transitions of $iso$-propyl cyanide, (CH$_3$)$_2$CHCN, also known as $iso$-butyronitrile, were recorded using long-path absorption spectroscopy in selected regions between 37 and 600 GHz. Further measurements were carried out…
Topological and geometrical methods are used to calculate the pseudorotational part of the vibronic spectrum for an electronic triplet of an octahedral, tetrahedral, or icosahedral molecule. The calculations take into account the nontrivial…
Rotational spectra of diatomic molecules measured in the high-precision experiments are analyzed. Such a spectrum is usually fitted by an 8th order polynomial in spin. In fact, from the theoretical point of view, the rotational spectrum is…
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…
Methyl mercaptan (CH$_3$SH) is an important sulfur-bearing species in the interstellar medium, terrestrial environment, and potentially in planetary atmospheres. The aim of the present study is to provide accurate spectroscopic parameters…
We synthesized the astrochemically relevant molecule 3-hydroxypropanal (HOCH$_2$CH$_2$CHO) and subsequently measured and analyzed its rotational spectrum in several frequency regions ranging from 130 to 485 GHz. We analyzed the ground…
We use an optical centrifuge to excite coherent rotational wave packets in N$_2$O, CS$_2$ and OCS molecules with rotational quantum numbers reaching up to J=465, 690 and 1186, respectively. Time-resolved rotational spectroscopy at such…