This database contains the rotational spectral lines observed and reported in the open literature for 121 diatomic molecules through July 2002. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty, and reference are given for each transition reported. Derived molecular properties, such as rotational constants, hyperfine structure constants, electric dipole moments, rotational g-factors and internuclear distances, are listed with one standard deviation uncertainties for all species.

This database contains the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules through September 1987. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported. In addition to correcting a number of misprints and errors in the literature cited, the spectral lines for many normal isotopic species have been refit to produce a comprehensive and consistent analysis of all the data extracted from various literature sources. The derived molecular properties, such as rotational and centrifugal distortion constants, hyperfine structure constants, electric dipole moments, and rotational g-factors are listed.

This database contains critically evaluated transition frequencies for the molecular transitions detected in interstellar and circumstellar clouds reported in the literature through mid-2008. The tabulated transition frequencies are recommended for reference in future astronomical observations in the centimeter and millimeter wavelength regions. The transition frequencies have been selected through a critical examination and analysis of the laboratory spectral data obtained from the literature. The information tabulated includes the species identity, transition frequency, uncertainty, and quantum state labels. For convenience, representative line antenna temperatures are listed for a typical astronomical source for each transition, and the references are cited for the laboratory and astronomical literature that have been employed. 2009 Revision

Wavenumber Calibration Tables from Heterodyne Frequency Measurements contains tables of gas-phase infrared transition wavenumbers and their spectroscopic assignments that are appropriate for calibrating high-spectral-resolution infrared spectrometers. The calibration lines for carbonyl sulfide (OCS), nitrous oxide (N2O), nitric oxide (NO), carbonyl sulfide (CS2), and carbon monoxide (CO) collectively extend from approximately 486 wavenumber (cm-1) to 4355 wavenumbers (cm-1) in the infrared. The bibliography and spectral atlas are current through November 1994. The bibliography covers a range of high-resolution spectroscopic studies on the calibration molecules listed above, including pressure broadening studies.

This database provides theoretical values of energy levels of hydrogen and deuterium for principle quantum numbers n = 1 to 200 and all allowed orbital angular momenta l and total angular momenta j. The values are based on current knowledge of the relevant theoretical contributions including relativistic, quantum electrodynamic, recoil, and nuclear size effects.

This database provides critical atomic and molecular data needed in order to evaluate the feasibility of using laser cooled and trapped Group II atomic species (Mg, Ca, Sr, and Ba) for ultra-precise optical clocks or quantum information processing devices.

This data collection contains 5,228 infrared spectra of different compounds along with chemical structures for most of them. Spectra are provided on a CD-ROM in the JCAMP-DX (Joint Committee for Atomic and Molecular Physical Data 'Data Exchange') format. Chemical structures are provided in the MOL-file format. The IR data originated from two sources, from the so-called 'EPA Vapor-Phase IR Library' and from NIST laboratories. The data have been sub-divided in two ways: 1) as concatenated JCAMP and SDF files (concatenated MOL-files) and 2) in individual files where each spectrum and structure is provided in a separate JCAMP and MOL file, using file names containing the CAS registry number of the compound. Important Note: All spectra were measured in the gas phase by GC/IR (gas chromatography/infrared spectroscopy), hence concentrations in the IR cell are not known or estimable. Molar absorption coefficients are not reported. This data provides only relative absorption coefficients as a function of wavelength which can be used for identification, not quantification.

This data collection contains 5,228 infrared spectra of different compounds along with chemical structures for most of them. Spectra are provided on a CD-ROM in the JCAMP-DX (Joint Committee for Atomic and Molecular Physical Data 'Data Exchange') format. Chemical structures are provided in the MOL-file format. The IR data originated from two sources, from the so-called 'EPA Vapor-Phase IR Library' and from NIST laboratories. The data have been sub-divided in two ways: 1) as concatenated JCAMP and SDF files (concatenated MOL-files) and 2) in individual files where each spectrum and structure is provided in a separate JCAMP and MOL file, using file names containing the CAS registry number of the compound. Important Note: All spectra were measured in the gas phase by GC/IR (gas chromatography/infrared spectroscopy), hence concentrations in the IR cell are not known or estimable. Molar absorption coefficients are not reported. This data provides only relative absorption coefficients as a function of wavelength which can be used for identification, not quantification.

This dataset contains the data for the figures in the paper "EIT spectra of Rydberg atoms dressed with dual tone radio-frequency fields", submitted to Physical Review A. This dataset can be used to recreate the experimental and theory plots from the CSV files. The data show EIT spectra of Rydberg atoms driven with dual-tone RF fields (experimental), and Floquet spectra of numerical models that are used to model these EIT spectra (theory/numerical). The data demonstrate spectra of driven Rydberg atoms in the strong field regime, and the models demonstrate the applicability of two-level Floquet spectra to reproduce the dominant spectral features.

CO2 is studied using dispersed synchrotron radiation in the 650 Å and 840 Å spectral region. The vibrationally resolved photoelectron spectra are analyzed to generate relative vibrational transition amplitudes and the angular asymmetry parameters describing the various transitions observed.