The submillimeter spectrum of CrH and CrD (X6Σ +)

D. T. Halfen, L. M. Ziurys

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


The N = 0 → 1 rotational transition of CrH and the N = 1 → 2 transition of CrD have been recorded in their X6L+ ground electronic states using submillimeter direct absorption spectroscopy. Both species were created in a DC discharge by the reaction of chromium metal, vaporized in a Broida-type oven, with H2 or D2. Because of the presence of five unpaired electrons, as well as the proton or deuterium nuclear spin, these transitions exhibit complicated fine structure and hyperfine splittings. The five strongest hyperfine transitions were measured for CrH and are split over a 60 GHz region because of spin-spin and spin-rotation interactions. Seven lines have also been recorded for CrD arising from four spin components. The data have been analyzed with a Hund's case b Hamiltonian, resulting in improved constants for both species. These data are crucial for submillimeter searches for CrH toward interstellar and circumstellar gas. Electronic transitions of CrH have been routinely observed in L dwarf and brown dwarf atmospheres, suggesting its presence in other astronomical regions.

Original languageEnglish (US)
Pages (from-to)L65-L68
JournalAstrophysical Journal
Issue number1 II
StatePublished - Aug 10 2004


  • Astrochemistry
  • ISM: molecules
  • Line: identification
  • Methods: laboratory
  • Molecular data
  • Stars: AGB and post-AGB

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'The submillimeter spectrum of CrH and CrD (X6Σ +)'. Together they form a unique fingerprint.

Cite this