What's new?

And what is not quite so new anymore?

The database is described in

and in

Please acknowledge use of the CDMS by citing these article. You are very welcome to state the web address also. We recommend to cite the original sources of the data too, which are given in the documentations, at least as far as this is feasible.

Earlier Catalog Entries

• Apr. 2024: HCCNC; DCCNC; HCCN¹³C; HC¹³CNC; H¹³CCNC; HCC¹⁵NC; DNC₃; HNCC¹³C; HNC¹³CC; HN¹³CCC; cis-HSNO; trans-HSNO.
• Feb. 2024: HNSiO; HPCO; HSiCCH; H₂C₃Si; H₂C₄Si; HCNH⁺.
• Jan. 2024: HNSO; H₂NC₃N; E-2-butenenitrile; syn-3-butenenitrile; gauche-3-butenenitrile.
• Dec. 2023: D₂CS; C₆H, v = 0; C₆H, v₁₁ = 1 μΣ; C₆H, v₁₁ = 1 Δ; isobutene.
• Nov. 2023: CD₃OD, v_t = 0; CD₃OD, v_t = 1; SO¹⁸O; CH₃C(NH)CH₃; trans-HONO; cis-HONO.
• Oct. 2023: H₂CS, v₄ = 1; H₂CS, v₆ = 1; H₂CS, v₃ = 1; H₂CS, v₂ = 1; H₂CS, υ₄ IR band; H₂CS, υ₆ IR band; H₂CS, υ₃ IR band; H₂CS, υ₂ IR band; allylimine-Ta; H₂C₂S; CN⁺, v = 0; CN⁺, v = 1 − 0.
• Sep. 2023: C₁₀H⁻; SiCl⁺, v = 0, 1; CHD₂CHO, v_t = 0; c-C₃H₂D⁺; extended CHD₂OH entry in frequency.
• Aug. 2023: H₂C₃H⁺; SiF⁺, v = 0, 1; SiF⁺, v = 1 − 0, 2 − 1; SiF⁺, v = 2 − 0; ²⁹SiF⁺, v = 0; ³⁰SiF⁺, v = 0.
• Jul. 2023: NO⁺, v = 0, 1; NO⁺, v = 1 − 0, 2 − 1; NO⁺, v = 2 − 0; HC₃O⁺.

• Nov. 2023: The information on the meaning of lower case characters as quantum numbers was misleading and has been rephrased. The term g_I was missing in several “useful equations” because it was assumed to be 1 initially.
• Mar. 2019: The program of the VAMDC-CDMS was updated. The Classic or ascii-CDMS was moved to this server. Links have been corrected and should work, but a detailed check is pending. The coding of special characters has been adjusted.
• Nov. 2009: added note in the link which explains the aggregate spin number.

Archive "Catalog Search Form"

• Nov. 2021: A new group was defined: Other hydrocarbons, that are hydrocarbons different from the carbon chain species C_nH and C_nH₂, but including isotopologs.

• Apr. 2010: started to add values at 2.725 and 5 K for some species. The log values are also displayed in the partition function table.

Archive "Molecules in Space"

• Apr. 2024: added thioxyhydroxymethylium and thionylimide with documentations; updated HCCNC, HNC₃, and HNCS documentations.
• Mar. 2024: added extragalactic protonated acetylene with documentation; updated H₂O documentation.
• Feb. 2024: added HCNS with documentation. Updated HNCS, HSCN, HNCO, and HCNO documentations.
• Jan. 2024: updated SiC₂ documentation. The 2-butenenitrile species are counted as two because mutual conversion requires breaking of a (double) bond, hence, the E- and Z-species are different isomers, not conformers.
• Dec. 2023: added isobutene with documentation.
• Nov. 2023: added FeC with documentation.
• Sep. 2023: added methylium and ethynylbenzene with documentation; updated C₁₀H⁻, methylamine, and methyl isocyanide.
• Aug. 2023: added H₂C₃N, carbonic acid, and glycolamide with documentations.
• Jul. 2023: added E-CH₂(CH)₃CN and H₂C₃H⁺ with documentations.

Archive "Fitting Spectra"

• Dec. 2020: added aminoacetonitrile example.
• Nov. 2020: added hydroxymethyl data.

Archive "Cologne Spectroscopy Data"

• Jan. 2024: isobutene files are complete.
• Sep. 2023: added new H₂CS files with H₂C₂S.
• Jun. 2023: added CCl⁺ files.
• May 2023: added CH₃NHCH₃ files.
• Apr. 2023: added c-CD₂CH₂O files.