Molecules in Protoplanetary Disks


INITIATED JULY 2018: This is a list of molecules that have been found in protoplanetary/circumstellar disks, such as TW Hydrae (above left) and HL Tauri (above right). The list below also includes isotopomeric variants that have been detected in protoplanetary disks.

	For background about chemistry in protoplanetary disks, see the archived presentation by Öberg et al. or the 2013 review paper by Henning & Semenov.

Initial detections are given first; a number of surveys are given at the bottom of the page.

INITIAL DETECTIONS
YEAR	SPECIES	CITATION	SOURCE AND LINES
1993	¹³CO carbon monoxide	A Rotating Gaseous Disk around the T Tauri Star GM Aurigae D. W. Koerner, A. I. Sargent, and S. V. W. Beckwith. Icarus 106:2-10 (1993).	GM Aurigae J = 2-1 (220.4 GHz)
1997	CN cyano radical	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	GG Tauri, DM Tauri 1-0 2-1
1997	HCN hydrogen cyanide	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	GG Tauri, DM Tauri 1-0 3-2
1997	HNC hydrogen isocyanide	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	GG Tauri, DM Tauri ???
1997	CS carbon monosulfide	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	GG Tauri, DM Tauri 3-2 5-4
1997	HCO⁺ protonated CO	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	GG Tauri, DM Tauri 1-0 3-2
1997	N₂H⁺ protonated N₂	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	GG Tauri, DM Tauri 1-0
1997	H₂CO formaldehyde	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	GG Tauri, DM Tauri 2₀₂-1₀₁ 2₁₂-1₁₁ 3₁₂-2₁₂
1997	C₂H ethynyl	Chemistry of protosolar-like nebulae: The molecular content of the DM Tau and GG Tau disks A. Dutrey, S. Guilloteau, and M. Guélin. A&A 317:L55-L28 (1997).	DM Tauri 1-0
2001	CO carbon monoxide	H₂ and CO emisision from disks around T Tauri and Herbig Ae pre-main sequence stars and from debris disks around young stars: Warm and cold circumstellar gas W. F. Thi, E. F. van Dishoeck, G. A. Blake, G. J. van Zadelhoff, J. Horn, E. E. Becklin, V. Mannings, A. I. Sargent, M. F. van den Ancker, A. Natta, and J. Kessler. ApJ 561:1074-1094 (2001).	Multiple sources 3-2 6-5
2003	DCO⁺ protonated CO	Detection of DCO⁺ in a circumstellar disk E. F. van Dishoeck, W.-F. Thi, and G.-J. van Zadelhoff. A&A 400:L1-L4 (2003).	TW Hydrae J = 5-4 (360.169 GHz)
2008	DCN hydrogen cyanide	Resolving the Chemistry in the Disk of TW Hydrae. I. Deuterated Species C. Qi, D. J. Wilner, Y. Aikawa, G. A. Blake, and M. R. Hogerheijde. ApJ 681:1396-1407.	TW Hydrae J = 3-2 (217.23863 GHz)
2011	H₂O water	Detection of the Water Reservoir in a Forming Planetary System M. R. Hogerheijde, E. A. Bergin, C. Brinch, L. I. Cleeves, J. K. J. Fogel, G. A. Blake, C. Dominik, D. C. Lis, G. Melnick, D. Neufeld, O. Panić, J. C. Pearson, L. Kristensen, U. A. Yıldız, and E. F. van Dishoeck. Science 334:338-340 (2011).	TW Hydrae 1₁₀-1₀₁ (ortho) 1₁₁-1₀₀ (para)
2011	H¹³CO⁺ protonated CO	The Ionization Fraction in the DM Tau Protoplanetary Disk K. I. Öberg, C. Qi, D. J. Wilner, and S. M. Andrews. ApJ 743:152 (2011). (first detection?)	DM Tau J = 3-2 (260.255 GHz)
2012	HC₃N cyanoacetylene	Chemistry in Disks. VII. First Detection of HC₃N in Protoplanetary Disks E. Chapillon, A. Dutrey, S. Guilloteau, V. Piétu, V. Wakelam, F. Hersant, F. Gueth, T. Henning, R. Launhardt, K. Schreyer, and D. Semenov. ApJ 756:58 (2018).	MWC 480... (16-15) (145.560 GHz) (12-11) (109.173 GHz) (10-9) (90.978 GHz)
2013	HD hydrogen	An old disk still capable of forming a planetary system E. A. Bergin, L. I. Cleeves, U. Gorti, K. Zhang, G. A. Blake, J. D. Green, S. M. Andrews, N. J. Evans II, T. Henning, K. Öberg, K. Pontoppidan, C. Qi, C. Salyk, and E. F. van Dishoeck. Nature 493:644-646 (2013).	TW Hya 1-0 (~112 μm)
2013	SO sulfur monoxide	A sensitive survey for ¹³CO, CN, H₂CO, and SO in the disks of T Tauri and Herbig Ae stars S. Guilloteau, E. Di Folco, A. Dutrey, M. Simon, N. Grosso, and V. Piétu. A&A 549, A92 (2013). Chemistry in disks. X. The molecular content of protoplanetary disks in Taurus S. Guilloteau, L. Reboussin, A. Dutrey, E. Chapillon, V. Wakelam, V. Piétu; E Di Folco, D. Semonov, and T. Henning. A&A 592:A125 (2016).	Multiple sources 5₄-4₃ (206.176062 GHz) 6₅-5₄ (251.825816 GHz) 6₇-5₆ (261.843756 GHz)
2013	c-C₃H₂ cyclo- propenylidene	First Detection of c-C₃H₂ in a Circumstellar Disk C. Qi, K. I. Öberg, D. J. Wilner, and K. A. Rosenfeld. ApJL 765:L14 (2013).	HD 163296 3_3,0-2_2,1 (216.279 GHz) 6_1,6-5_0,5/6_0,6-5_1,5 (217.822 GHz) 5_1,4-4_2,3 (217.940 GHz)
2015	CH₃CN methyl cyanide	The comet-like composition of a protoplanetary disk as revealed by complex cyanides K. I. Öberg, V. V. Guzmán, K. Furuya, C. Qi, Y. Aikawa, S. M. Andrews, R. Loomis, and D. J. Wilner. Nature 520:198-200 (2015).	MWC 480 14₀-13₀ (257.5274 GHz) 14₁-13₁ (257.5224 GHz)
2015	N₂D⁺ protonated nitrogen	Detection of N₂D⁺ in a protoplanetary disk J. Huang and K. I. Öber. ApJL 809:L26 (2015).	AS 209 3-2 (231.39868 MHz)
2015	H¹³CN hydrogen cyanide	Cyanide photochemistry and nitrogen fractionation in the MWC 480 disk V. V. Guzmán, K. I. Öberg, R. Loomis, and C. Qi. ApJ 814:53 (2015).	MWC 480 3-2 (259.0118 GHz)
2015	HC¹⁵N hydrogen cyanide	Cyanide photochemistry and nitrogen fractionation in the MWC 480 disk V. V. Guzmán, K. I. Öberg, R. Loomis, and C. Qi. ApJ 814:53 (2015).	MWC 480 3-2 (258.1571 GHz)
2016	CH₃OH methanol	First Detection of Gas-phase Methanol in a Protoplanetary Disk C. Walsh, R. A. Loomis, K. I. Öberg, M. Kama, M. L. R. van't Hoff, T. J. Millar, Y. Aikawa, E. Herbst, S. L. Widicus Weaver, and H. Nomura. ApJL 832:L10 (2016).	TW Hydrae 7 lines
2016	NH₃ ammonia	First detection of gas-phase ammonia in a planet-forming disk. NH₃, N₂H⁺, and H₂O in the disk around TW Hydrae V. N. Salinas, M. R. Hogerheijde, E. A. Bergin, L. I. Cleeves, C. Brinch, G. A. Blake, D. C. Lis, G. J. Melnick, O. Panić, J. C. Pearson, L. Kristensen, U. A. YĲldĲz, and E. F. van Dishoeck. A&A 591:A122 (2016).	TW Hydrae 1₀-0₀ (572.49817 GHz)
2017	C¹⁵N cyano radical	Direct evidence of multiple reservoirs of volatile nitrogen in a protosolar nebula analog P. Hily-Blant, V. Magalhaes, J. Kastner, A. Faure, T. Forveille, and C. Qi. A&A 603:L6 (2017).	TW Hydrae 3-2 with hyperfine
2018	t-HCOOH trans-formic acid	First Detection of the Simplest Organic Acid in a Protoplanetary Disk C. Favre, D. Fedele, D. Semenov, S. Parfenov, C. Codella, C. Ceccarelli, E. A. Bergin, E. Chapillon, L. Testi, F. Hersant, B. Lefloch, F. Fontani, G. A. Blake, L. I. Cleeves, C. Qi, K. R. Schwarz, and V. Taquet. ApJL 862:L2 (2018).	TW Hydrae 6_(1-6)5_(1,5) (129 GHz)
2018	H₂S hydrogen sulfide	First detection of H₂S in a protoplanetary disk. The dense GG Tauri A ring N. T. Phuong, E. Chapillon, L. Majumdar, A. Dutrey, S. Guilloteau, V. Piétu, V. Wakelam, P. N. Diep, Y.-W. Tang, T. Beck, and J. Bary. A&A 616:L5 (2018).	GG Tauri 1_1,0-1_0,1
2019	¹³CS carbon monosulfide	Sulfur Chemistry in Protoplanetary Disks: CS and H₂CS R. Le Gal, K. I. Öberg, R. A. Loomis, J. Pegues, and J. B. Bergner. ApJ 876:72 (2019).	LkCa 15 MWC 480 6-5
2019	C³⁴S carbon monosulfide	Sulfur Chemistry in Protoplanetary Disks: CS and H₂CS R. Le Gal, K. I. Öberg, R. A. Loomis, J. Pegues, and J. B. Bergner. ApJ 876:72 (2019).	LkCa 15 6-5
2019	H₂CS thioformaldehyde	Sulfur Chemistry in Protoplanetary Disks: CS and H₂CS R. Le Gal, K. I. Öberg, R. A. Loomis, J. Pegues, and J. B. Bergner. ApJ 876:72 (2019).	MWC 480 8₁₇-7₁₆ 9₁₉-8₁₈ 9₁₈-8₁₇
2019	¹³C¹⁷O carbon monoxide	The First Detection of ¹³C¹⁷O in a Protoplanetary Disk: A Robust Tracer of Disk Gas Mass A. S. Booth, C. Walsh, J. D. Ilee, S. Notsu, C. Qi, H. Nomura, and E. Akiyama. ApJL 882:L31 (2019).	HD 163296 blend of 14 hyperfine transitions of J=3-2(321.851-321.852 GHz)
2022	HC¹⁸O⁺ protonated CO	Detection of HC¹⁸O⁺ in a Protoplanetary Disk: Exploring Oxygen Isotope Fractionation of CO K. Furuya, T. Tsukagoshi, C. Qi, H. Nomura, L. I. Cleeves, S. Lee, and T. C. Yoshida. ApJ 926:148 (2022).	TW Hydrae 4-3 (340.6329780 GHz)
2022	CH₃OCH₃ dimethyl ether	A major asymmetric ice trap in a planet-forming disk - III. First detection of dimethyl ether N. G. C. Brunken, A. S. Booth, M. Leemker, P. Nazari, N. van der Marel, and E. F. van Dishoeck. A&A 659:A29 (2022).	Oph IRS 48 various lines
2023	¹³CO₂ carbon dioxide	MINDS. The Detection of ¹³CO₂ with JWST-MIRI Indicates Abundant CO₂ in a Protoplanetary Disk S. L. Grant, E. F. van Dishoeck, B. Tabone, D. Gasman, T. Henning, I. Kamp, M. Güdel, P.-O. Lagage, G. Bettoni, G. Perotti, V. Christiaens, M. Samland et al. ApJL 947:L6 (2023).	GW Lup Q-branch lines
2023	C₆H₆ benzene	A rich hydrocarbon chemistry and high C to O ratio in the inner disk around a very low-mass star B. Tabone, G. Bettoni, E. F. van Dishoeck, A. M. Arabhavi, S. Grant, D. Gasman, T. Henning, I. Kamp, M. Güdel, P. O. Lagage, T. Ray, B. Vandenbussche et al. Nat Astron 7:805-814 (2023).	J160532 Q-branch lines
2023	C₄H₂ diacetylene	A rich hydrocarbon chemistry and high C to O ratio in the inner disk around a very low-mass star B. Tabone, G. Bettoni, E. F. van Dishoeck, A. M. Arabhavi, S. Grant, D. Gasman, T. Henning, I. Kamp, M. Güdel, P. O. Lagage, T. Ray, B. Vandenbussche et al. Nat Astron 7:805-814 (2023).	J160532 Q-branch lines
2023	CH₃⁺ methyl cation	Formation of the methyl cation by photochemistry in a protoplanetary disk O. Berné, M.-A. Martin-Drumel, I. Schroetter, J. R. Goicoechea, U. Jacovella, B. Gans, E. Dartois, L. H. Coudert, E. Bergin, F. Alarcon, J. Cami, E. Roueff, J. H. Black, O. Asvany, E. Habart, E. Peeters, A. Canin, B. Trahin, C. Joblin, S. Schlemmer, S. Thorwirth, J. Cernicharo, M. Gerin, A. Tielens, M. Zannese et al. Nature 621:56-59 (2023).	d203-506 ro-vibrational structure of v₂ and v₄ transitions

SURVEYS
YEAR	SPECIES	CITATION	SOURCES
2010	H₂O OH C₂H₂ HCN CO₂	*A Spitzer* Survey of Mid-infrared Molecular Emission from Protoplanetary Disks. I. Detection Rates.** K. M. Pontoppidan, C. Salyk, G. A. Blake, R. Meijerink, J. S. Carr, and J. Najita. ApJ 720:887 (2010).	48 T Tauri stars 25 Herbig Ae/Be stars
2011	H₂O OH C₂H₂ HCN CO₂	*A Spitzer* Survey of Mid-infrared Molecular Emission from Protoplanetary Disks. II. Correlations and Local Thermal Equilibrium Models** C. Salyk, K. M. Pontoppidan, G. A. Blake, J. R. Najita, and J. S. Carr. ApJ 731:130 (2011).	48 T Tauri stars 25 Herbig Ae/Be stars
2020	H₂CO	An ALMA Survey of H₂CO in Protoplanetary Disks J. Pegues, K. I. Öberg, J. B. Bergner, R. A. Loomis, C. Qi, R. Le Gal, L. I. Cleeves, V. V. Guzmán, J. Huang, J. K. Jørgensen, S. M. Andrews, G. A. Blake, J. M. Carpenter, K. R. Schwarz, J. P. Williams, and D. J. Wilner. ApJ 890:142 (2020).	15 disks
2020	HCN	Probing UV-sensitive Pathways for CN and HCN Formation in Protoplanetary Disks with the Hubble Space Telescope N. Arulanantham, K. France, P. Cazzoletti, A. Miotello, C. F. Manara, P. C. Schneider, K. Hoadley, E. F. van Dishoeck, and H. M. Günther. AJ 159:168 (2020).	5 Lup and 14 Tau-Aur disks
2020	H₂O HCN C₂H₂ CO₂	Hints for Icy Pebble Migration Feeding an Oxygen-rich Chemistry in the Inner Planet-forming Region of Disks A. Banzatti, I. Pascucci, A. D. Bosman, P. Pinilla, C. Salyk, G. J. Herczeg, K. M. Pontoppidan, I. Vazquez, A. Watkins, S. Krijt, N. Hendler, and F. Long. ApJ 903:124 (2020).	63 disks
2020	H₂CS	ALMA chemical survey of disk-outflow sources in Taurus (ALMA-DOT) - IV. Thioformaldehyde (H₂CS) in protoplanetary discs: spatial distributions and binding energies C. Codella, L. Podio, A. Garufi, J. Perrero, P. Ugliengo, D. Fedele, C. Favre, E. Bianchi, C. Ceccarelli, S. Mercimek, F. Bacciotti, K. L. J. Rygl, and L. Testi. A&A 644:A120 (2020).	5 Tau disks
2021	¹²CO ¹³CO C¹⁸O C₂H H₂CO HCN DCN	An Atacama Large Millimeter/submillimeter Array Survey of Chemistry in Disks around M4-M5 Stars J. Pegues, K. I. Öberg, J. B. Bergner, J. Huang, I. Pascucci, R. Teague, S. M. Andrews, . A. Bergin, L. I. Cleeves, V. V. Guzmán, F. Long, C. Qi, and D. J. Wilner. ApJ 911:150 (2021).	5 disks
2021	¹²CO ¹³CO C¹⁸O	An ALMA Survey of Protoplanetary Disks in Lynds 1641 S. L. Grant, C. C. Espaillat, J. Wendeborn, J. J. Tobin, E. Macías, A. Rilinger, Á. Ribas, S. T. Megeath, W. J. Fischer, N. Calvet, and K. H. Kim. ApJ 913:123 (2021).	101 disks

uv-vis (electronic) mm/sub-mm (rotational) infrared (vibrational)

Maintained by DE Woon

Updated 31 May 2024