Duo: a general program for calculating spectra of diatomic molecules

Abstract

Duo is a general, user-friendly program for computing rotational, rovibrational and rovibronic spectra of diatomic molecules. Duo solves the Schrödinger equation for the motion of the nuclei not only for the simple case of uncoupled, isolated electronic states (typical for the ground state of closed-shell diatomics) but also for the general case of an arbitrary number and type of couplings between electronic states (typical for open-shell diatomics and excited states). Possible couplings include spin-orbit, angular momenta, spin-rotational and spin-spin. Corrections due to non-adiabatic effects can be accounted for by introducing the relevant couplings using so-called Born-Oppenheimer breakdown curves. Duo requires user-specified potential energy curves and, if relevant, dipole moment, coupling and correction curves. From these it computes energy levels, line positions and line intensities. Several analytic forms plus interpolation and extrapolation options are available for representation of the curves. Duo can refine potential energy and coupling curves to best reproduce reference data such as experimental energy levels or line positions. Duo is provided as a Fortran 2003 program and has been tested under a variety of operating systems.

References in corpus (11)

• The ExoMol database: molecular line lists for exoplanet and other hot atmospheres
• ExoMol molecular line lists V: The ro-vibrational spectra of NaCl and KCl
• ExoMol molecular line lists: IX The spectrum of AlO
• ExoMol molecular line lists - XIII: The spectrum of CaO
• The {\it ab initio} calculation of spectra of open shell diatomic molecules
• Nonadiabatic corrections to the wave function and energy
• Inverse Quantum Chemistry: Concepts and Strategies for Rational Compound Design
• Radiative lifetimes and cooling functions for astrophysically important molecules
• The calculated rovibronic spectrum of scandium hydride, ScH
• Avoided crossings between bound states of ultracold Cesium dimers
• Hybrid variation-perturbation method for calculating rovibrational energy levels of polyatomic molecules

Cited by in corpus (69)

• The ExoMol database: molecular line lists for exoplanet and other hot atmospheres
• ExoMol Molecular linelists -- XXXIII. The spectrum of Titanium Oxide
• The 2020 release of the ExoMol database: molecular line lists for exoplanet and other hot atmospheres
• ExoMol line lists XVIII. The high temperature spectrum of VO
• ExoCross: a general program for generating spectra from molecular line lists
• ExoMol molecular line lists - XIV: The rotation-vibration spectrum of hot SO${}_2$
• Spectroscopic line parameters of NO, NO${}_2$, and N${}_2$O for the HITEMP database
• ExoMol molecular line lists - XXIII: spectra of PO and PS
• The ExoMol project: Software for computing large molecular line lists
• ExoMol line lists XXIV: A new hot line list for silicon monohydride, SiH
• ExoMol Line List XXI: Nitric Oxide (NO)
• The {\it ab initio} calculation of spectra of open shell diatomic molecules
• The ExoMol Atlas of Molecular Opacities
• ExoMol line lists XXVIII: The rovibronic spectrum of AlH
• ExoMol line lists -- XLIV. IR and UV line list for silicon monoxide (SiO)
• ExoMol line lists XXXI: Spectroscopy of lowest eights electronic states of C${}_2$
• MARVEL analysis of the measured high-resolution rovibronic spectra of ${}^{48}$Ti${}^{16}$O
• The spectrum of N${}_2$ from 4,500 to 15,700 cm${}^{-1}$ revisited with PGOPHER
• Laboratory spectra of hot molecules: data needs for hot super-Earth exoplanets
• Sub-promille measurements and calculations of CO (3--0) overtone line intensities
• Experimental energy levels and partition function of the ${}^{12}$C${}_2$ molecule
• ExoMol line lists - XXXII. The rovibronic spectrum of MgO
• Full Spectroscopic Model and Trihybrid Experimental-Perturbative-Variational Line List for CN
• ExoMol molecular line lists XXXVI: $X{}^2\Pi -X{}^2\Pi$ and $A{}^2{\Sigma }^{+}-X{}^2\Pi$ transitions of SH
• An update to the MARVEL dataset and ExoMol line list for 12C2
• ExoMol molecular line lists - XXVI: spectra of SH and NS
• ExoMol molecular line lists -- XLII: Rovibronic molecular line list for the low-lying states of NO
• A high-resolution line list for AlO
• Assessing Spectra and Thermal Inversions due to TiO in Hot Jupiter Atmospheres
• Calculation of Electric Quadrupole Linestrengths for Diatomic Molecules: Application to the H2, CO, HF and O2 Molecules
• Spectroscopy of YO from first principles
• ExoMol line lists -- XLV. Rovibronic molecular line lists of calcium monohydride (CaH) and magnesium monohydride (MgH)
• ExoMol line lists -- LVI: The SO line list, MARVEL analysis of experimental transition data and refinement of the spectroscopic model
• Predicted Landé $g$-factors for open shell diatomic molecules
• Predissociation dynamics of the hydroxyl radical (OH) based on a five-state spectroscopic model
• Ab initio calculations to support accurate modelling of the rovibronic spectroscopy calculations of vanadium monoxide (VO)
• Empirical Line Lists in the ExoMol Database
• An ab initio study of the rovibronic spectrum of sulphur monoxide (SO): diabatic vs. adiabatic representation
• ExoMol photodissociation cross sections I: HCl and HF
• ExoMol line list XXXIV: A Rovibrational Line List for Phosphinidene (PH) in its $X{}^3{\Sigma }^{-}$ and $a{}^1\Delta$ Electronic States
• Quantitative theoretical analysis of lifetimes and decay rates relevant in laser cooling BaH
• AlH lines in the blue spectrum of Proxima Centauri
• A method for the variational calculation of hyperfine-resolved rovibronic spectra of diatomic molecules
• Analysis of the TiO isotopologues in stellar optical spectra
• The Rotationally Resolved Infrared Spectrum of TiO and Its Isotopologues
• Rovibronic spectroscopy of PN from first principles
• ExoMol molecular line lists -- XLIII: Rovibronic molecular line list the low-lying two states of NaO
• Low-temperature chemistry using the R-matrix method
• Full Spectroscopic Model and Trihybrid Experimental-Perturbative-Variational Line List for ZrO
• High-throughput Quantum Chemistry: Empowering the Search for Molecular Candidates behind Unknown Spectral Signatures in Exoplanetary Atmospheres
• A spectroscopic model for the low-lying electronic states of NO
• Ab initio relativistic treatment of the intercombination $a^3\Pi -X^1{\Sigma }^{+}$ Cameron system of the CO molecule
• Ab initio Study of Ground-State CS Photodissociation Via Highly Excited Electronic States
• Fourier transform spectroscopy, relativistic electronic structure calculation, and coupled-channel deperturbation analysis of the fully mixed $A^1{\Sigma }_u^{+}$ and $b^3{\Pi }_u$ states of Cs${}_2$
• A variational model for the hyperfine resolved spectrum of VO in its ground electronic state
• Molecular diatomic spectroscopy data
• Assignment of excited-state bond lengths using branching-ratio measurements: The B${}^2{\Sigma }^{+}$ state of BaH molecules
• Diatomic rovibronic transitions as potential probes for proton-to-electron mass ratio across cosmological time
• ExoMol line lists -- {XLVI}: Empirical rovibronic spectra of silicon mononitrate (SiN) covering the 6 lowest electronic states and 4 isotopologues
• Multireference configuration interaction study of the predissociation of C${}_2$ via its $F{}^1{\Pi }_u$ state
• ExoMol line lists -- LIII: Empirical Rovibronic spectra of Yttrium Oxide (YO)
• Low temperature scattering with the R-matrix method: argon-argon scattering
• The twofold diabatization of the KRb $(1\sim 2{)}^1\Pi$ complex in the framework of \emph{ab initio} and deperturbation approaches
• An empirical spectroscopic model for eleven electronic states of VO
• An ab initio spectroscopic model of the molecular oxygen atmospheric and infrared bands
• Transformative Applications of Machine Learning for Chemical Reactions
• High-Precision Quantum Dynamics of He${}_2$ over the b ${}^3{\Pi }_{\mathrm{g}}$-c ${}^3{\Sigma }_{\mathrm{g}}^{+}$ Electronic Subspace by including Non-adiabatic, Relativistic and QED Corrections and Couplings
• Low-temperature scattering with the R-matrix method: from nuclear scattering to atom-atom scattering and beyond
• Rovibrational computations for the He${}_2$ a ${}^3{\Sigma }_{\mathrm{u}}^{+}$ state including non-adiabatic, relativistic, and QED corrections