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Observed Interstellar Molecular Microwave Transitions, Table 1

Table 1. Listing by empirical formula of the isotopic forms of the 135 interstellar species detected by their microwave spectrum and appearing in Table 4

Empirical
Formula
Name Isotopic
Species
CA Number Reference
AlCN Aluminum isocyanide AlCN a [61192-70-9] Ziu02
AlCl Aluminum monochloride Al35Cl a [13595-81-8] Cer87c
Al37Cl a
AlF Aluminum monofluoride AlF a [13595-82-9] Cer87c
CF+ Flouromethyliumylidene CF+ [33412-11-2] Neu06
CH Methylidyne CH [3315-37-5] Ryd74, McK40 b
CHN Hydrocyanic acid (hydrogen cyanide) HCN [74-90-8] Sny71a
H13CN
HC15N
DCN
CHN Hydroisocyanic acid (hydrogen isocyanide) HNC [6914-07-4] Sny71
H15NC
HN13C
DNC
D15NC
CHNO Isocyanic acid HNCO [75-13-8] Sny71
DNCO
CHNS Isothiocyanic acid HNCS [3129-90-6] Fre79
CHO Oxomethyl (formyl) HCO [2597-44-6] Sny76
CHO+ Oxomethylium (formylium) HCO+ [17030-74-9] Buh70
H13CO+
HC17O+
HC18O+
DCO+
D13CO+
CHO+ Hydroxymethylidyne HOC+ [60528-75-8] Woo83, Ziu95a
CHO2+ Hydroxyoxomethylium HOCO+ [638-71-1] Tha81
CHP Phosphaethyne HCP [6829-52-3] Agú07
CHS+ Thiooxomethylium HCS+ [59348-25-3] Tha81
CH2 Methylene CH2 [2465-56-7] Hol89, Hol95
CH2N+ Iminomethylium HCNH+ [38263-97-7] Ziu86a
CH2N Methylene amidogen CH2N [15845-29-1] Ohi94
CH2N2 Cyanamide NH2CN [420-04-2] Tur75a
CH2O Formaldehyde (methanal) H2CO [50-00-0] Sny69
H213CO
H2C18O
HDCO
D2CO
CH2O2 Formic acid HCOOH [64-18-6] Zuc71, Win75
H13COOH
HCOOD
DCOOH
CH2S Methanethial (thioformaldehyde) H2CS [865-36-1] Sin73
H213CS
H2C34S
HDCS
D2CS
CH3 Methyl CH3a [2229-07-4] Feu00
CH3N Methanimine CH2NH [2053-29-4] God73
13CH2NH
CH3NO Formamide NH2CHO [75-12-7] Rub71
NH213CHO
CH3O+ Hydroxy methylium ion H2COH+ [17691-31-5] Ohi96
(protonated formaldehyde)
CH4O Methanol (methyl alcohol) CH3OH [67-56-1] Bal70
13CH3OH
CH318OH
CH2DOH
CH3OD
CHD2OH
CH4S Methanethiol (methyl mercaptan) CH3SH [74-93-1] Lin79
CH5N Methanamine (methylamine) CH3NH2 [74-89-5] Fou74a, Kai74
CMgN Magnesium cyanide MgCN a [74758-76-2] Ziu95
CMgN Magnesium isocyanide 24MgNC a [96491-22-4] Gue86, Gue93
25MgNC a
26MgNC a
CN Cyanogen CN [2074-87-5] Jef70, McK40 b
13CN
C15N
CNNa Sodium cyanide NaCN a [143-33-9] Tur94
CNSi Silicon cyanide SiCN a [29210-66-0] Gué00
CNSi Silicon isocyanide SiNC a [116430-49-0] Gué04
CO Carbon monoxide CO [630-08-0] Wil70
13CO
C17O
C18O
13C18O
13C17O
CO+ Carbon monoxide ion CO+ [12144-04-6] Eri81, Lat93
COS Carbon oxide sulfide (carbonyl sulfide) OCS [463-58-1] Jef71
OC34S
O13CS
18OCS
CO2 Carbon dioxide CO2 [124-38-9] Jus96
CP Carbon monophosphide CP a [12326-85-1] Sai89, Gue90
CS Carbon monosulfide CS [2944-05-0] Lis75
C33S
C34S
C36S
13CS
13CS34S
CSi Silicon monocarbide SiC a [409-21-2] Cer89
C2H Ethynyl C2H [2122-48-7] Tuc78
13CCH
C13CH
C2D
C2HN Cyanomethylene HCCN [2612-62-6] Gue91
C2HNO Cyanoformaldehyde CNCHO   Rem08
C2H2N Cyanomethyl CH2CN [2932-82-3] Irv88a
C2H2O Ethanone (ketene) CH2CO [463-51-4] Tur77
C2H3N Acetonitrile (methyl cyanide) CH3CN [75-05-8] Sol71
13CH3CN
CH313CN
CH3C15N
CH2DCN
C2H3N Isocyanomethane (methyl isocyanide) CH3NC [593-75-9] Cer88
C2H3N Keteneimine (ethenimine) CH2CNH [17619-22-6] Lov06a
C2H4O Acetaldehyde (ethanal) CH3CHO [75-07-0] Got73
C2H4O Oxirane (ethylene oxide) c-C2H4O c [75-21-8] Dic97
C2H4O Ethenol (vinyl alcohol) a-CH2CHOH [557-75-5] Tur01
s-CH2CHOH
C2H4O2 Methyl ester formic acid (methyl formate) CH3OCHO [107-31-3] Bro75
C2H4O2 Acetic acid CH3COOH [64-19-7] Meh97
C2H4O2 Hydroxy acetaldehyde (glycolaldehyde) CH2OHCHO [141-46-8] Hol00
C2H5NO Acetamide CH3CONH2 [60-35-5] Hol06a
C2H6O trans-Ethanol (ethyl alcohol) t-CH3CH2OH [64-17-5] Zuc75
gauche-Ethanol g-CH3CH2OH Pea96
C2H6O Dimethyl ether (oxybismethane) CH3OCH3 [115-10-6] Sny74
C2H6O2 Ethylene glycol HOCH2CH2OH [107-21-1] Hol02
C2O Oxoethenylidene CCO [119754-08-4] Ohi91
C2P Phosphaethenylidene CCP [154474-31-4] Hal08
C2S Thioxoethenylidene CCS [109545-32-6] Yam90
CC34S
C2Si Silicon carbide (silacyclopropyne) SiC2 [12071-27-1] Tha84
29SiC2
30SiC2
Si13CC
C3 Tricarbon C3 [175780-10-6] Gie01
C3H Cyclopropenylidyne c-C3H b [16165-40-5] Yam87a
c-CC13CH
C3H Propenylidyne l-C3H d [53590-28-6] Tha85
C3HN 2-Propynenitrile (cyanoacetylene) HCCCN [1070-71-9] Tur71
H13CCCN
HC13CCN
HCC13CN
HCCC15N
DCCCN
C3HN Ethyne, isocyanide HCCNC [66723-45-3] Kaw92
C3HN 3-Imino-1,2-propadienylidene HNCCC [76092-41-6] Kaw92a
C3H2 Cyclopropenylidene c-C3H2c [16165-40-5] Mat85a
c-H13CCCH
c-HC13CCH
c-C3HD
C3H2 1,2-Propadienylidene H2CCC c [60731-10-4] Cer91
C3H2N+ Protonated 2-propynenitrile CCCNH+ [76092-42-7] Kaw94
C3H2O 2-Propynal HCCCHO [624-67-9] Irv88
C3H2O Cyclopropenone c-C2H2O [2966080-0] Hol06
C3H3N 2-Propenenitrile (vinyl cyanide) CH2CHCN [107-13-1] Gar75
13CH2CHCN
CH213CHCN
C3H4 1-Propyne (methyl acetylene) CH3CCH [74-99-7] Sny71
CH3C13CH
13CH3CCH
CH2DCCH
CH3CCD
C3H4O 2-Propenal (acrolein) CH2CHCHO [107-02-8] Hol04
C3H5N Propanenitrile (ethyl cyanide) CH3CH2CN [107-12-0] Joh77
CH3CH213CN
CH313CH2CN
13CH3CH2CN
C3H6 1-Propene (propylene) CH2CHCH3 [115-07-1] Mar07
C3H6O 2-Propanone (acetone) (CH3)2CO [67-64-1] Com87, Sny02
C3H6O 2-Propanal CH3CH2CHO [123-38-6] Hol04
C3N Cyanoethynyl CCCN [62435-43-2] Gue77
C3N- Cyanoethynyl anion CCCN- [12373-53-4] Tha08
C3O 3-Oxo-1,2-propadienylidene CCCO [11127-17-6] Mat84
C3S 3-Thioxo-1,2-propadienylidene CCCS [109545-35-9] Yam87
C3Si 3-Silanetetrayl-1,2-propadienylidene (rhomboidal SiC3) SiC3 [184291-25-1] App99
C4H 1,3-Butadiynyl radical C4H [53561-65-2] Gue77
13CCCCH
C13CCCH
CC13CCH
CCC13CH
C4D
C4H- 1,3-Butadiynyl anion C4H- [59012-21-4] Cer07
C4HN 3-Cyano-1,2-propadienylidene HCCCCN [847643-26-9] Bro84
C4H2 Butatrienylidene H2CCCC [70571-89-0] Bro84
C4H3N 2-Butynenitrile CH3CCCN [13752-78-8] Bro84
C4H3N Cyanoallene (2,3-butadienenitrile) CH2CCHCN [1001-56-5] Lov06
C4Si Silicon tetracarbide SiC4a [144920-67-2] Ohi89
SiCCC13C
C5H 2,4-Pentadiynylidyne HCCCCC [104602-63-3] Cer86
C5HN 2,4-Pentadiynenitrile (cyanobutadiyne) HCCCCCN [59866-32-9] Ave76
H13CCCCCN
HC13CCCCN
HCC13CCCN
HCCC13CCN
HCCCC13CN
DCCCCCN
C5H4 1,3-Pentadiyne (methyl diacetylene) CH3C4H [4911-55-1] Wal84
C5N 4-cyano-1,3-Butadiynylium C5N [129066-48-4] Gue98
C6H 1,3,5-hexatriynyl HCCCCCC [88053-50-3] Suz86
C6H- 1,3,5-hexatriynyl anion H-CCCCCC [169141-81-1] McC06
C6H2 1,3,5-Hexatriyne HCCCCCCH a [3161-99-7] Cer01a
C6H2 1,2,3,4,5-hexapentaenylidene H2CCCCCC [129066-05-3] Lan97
C6H3N 2,4-Hexadiynenitrile CH3C4CN [66486-69-9] Sny06
C7H 2,4,6-Heptatriynylidyne HCCCCCCC a [129066-03-1] Gue97
C7HN 2,4,6-heptatriynenitrile HC7N [65937-22-6] Kro78
C7H4 Methyltriacetylene CH3C6H [66486-68-8] Rem06
C8H 1,3,5,7-Octatetraynyl HC8a [88053-51-4] Cer96
C8H- 1,3,5,7-Octatetraynyl anion HC8- [149673-52-9] Brü07
C9HN 2,4,6,8-nonatetraynenitrile HC9N [67483-72-1] Bro78
C11HN 2,4,6,8,10-undecapentaynenitrile HC11N [78950-25-1] Bel97
ClH Hydrochloric acid H35Cl [7647-01-0] Sch95
H37Cl
ClK Potassium chloride K35Cl a [7447-40-7] Cer87c
K37Cl
ClNa Sodium chloride Na35Cl a [7647-14-5] Cer87c
Na37Cl a
FH Hydrogen fluoride HF [7664-39-3] Neu97
FeO Iron monoxide FeO [1345-25-1] Wal02
HLi Lithium Hydride 7LiH [7580-67-8] Com98
HNO Nitrosyl hydride HNO [14332-28-6] Uil77, Sny93
HN2+ Hydrodinitrogen(1+) (diazenylium) N2H+ [12357-66-3] Tur74, Gre74
15NNH+
N15NH+
N2D+
HO Hydroxyl OH [3352-57-6] Wei63
17OH
18OH
HS Mercapto (thiohydroxyl) SH [13940-21-1] Yam00
H2N Amidogen NH2 [13770-40-6] vDi93
H2O Water H2O [7732-18-5] Che69
H218O
HDO
D2O
H2S Hydrogen sulfide H2S [7783-06-4] Tha72
H234S
HDS
H3+ Hydrogen ion H2D+ [28132-48-1] Sta99
HD2+
H3N Ammonia NH3 [7664-41-7] Che68
15NH3
NH2D
NHD2
ND3
H3O+ Oxonium hydride H3O+ [28637-38-9] Hol86
H4Si Silane SiH4a [7803-62-5] Kea93
NO Nitrogen oxide (nitric oxide) NO [10102-43-9] Lis78a
NP Phosphorous nitride PN [17739-47-8] Tur87b
NS Nitrogen sulfide (nitric sulfide) NS [12033-56-6] Got75
N34S
NSi Silicon mononitride SiN a [12033-60-2] Tur92
N2O Nitrogen oxide (nitrous oxide) N2O [10024-97-2] Ziu94
OP Phosphorous oxide PO [14452-66-5] Ten07
OS Sulfur monoxide SO [13827-32-2] Got73b
33SO
34SO
S18O
OS+ Sulfur(1+), oxo SO+ [54724-05-9] Tur92a
OSi Silicon monoxide SiO [113443-18-8] Wil71
29SiO
30SiO
O2 Oxygen O2 [7782-44-7] Lar07
O2S Sulfur dioxide SO2 [7446-09-5] Sny75a
33SO2
34SO2
OS18O
OS17O
SSi Silicon monosulfide SiS [25423-24-9] Mor75
Si33S
Si34S
29SiS
30SiS

a Reported only in circumstellar clouds.
b Identification of the optical lines in McK40 were confirmed by W.S. Adams [Ada41].
c The c refers to cyclic form.
d The l refers to linear form.

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Created June 13, 2018, Updated November 15, 2019