Excitation of Molecules and Atoms for Astrophysics (EMAA): A spectroscopic and collisional database

Open Access

Table A.1

Collisional systems present in EMAA database as of June 29, 2025.

Molecule	Nuclear spin symmetry	Transition type	Projectiles	References
C(³P)		fine	ortho-H₂, para-H₂	Kłos et al. (2018)
C⁺(²P)		fine	ortho-H₂, para-H₂	Kłos et al. (2020b)
O(³P)		fine	H, He, ortho-H₂, para-H₂	Lique et al. (2017)
H₂		rovibration	H⁺	González-Lezana et al. (2021)
H₂		rovibration	ortho-H₂, para-H₂	Flower et al. (2000)
H₂		rovibration	H	Lique (2015)
H₂		rovibration	electron	Flower et al. (2021)
HD		rovibration	H	Desrousseaux et al. (2022)
HD		rovibration	H⁺	González-Lezana et al. (2022)
HeH⁺		rotation	H	Desrousseaux & Lique (2020)
HeH⁺		rotation	electron	Hamilton et al. (2015)
HeH⁺		rovibration	electron	Sil et al. (2025)
CH		hyperfine	He	Marinakis et al. (2019)
CH		hyperfine	H, ortho-H₂, para-H₂	Dagdigian (2018c)
CH⁺		rotation	H, electron	Faure et al. (2017)
¹³CH⁺		rotation	H	Faure et al. (2017)
¹³CH⁺		rotation	electron	Hamilton et al. (2015)
NH		hyperfine	ortho-H₂, para-H₂	Pirlot Jankowiak et al. (2024)
ND		hyperfine	ortho-H₂, para-H₂	Pirlot Jankowiak et al. (2024)
OH		hyperfine	ortho-H₂, para-H₂	Kłos et al. (2020a)
OH		fine	H	Dagdigian (2022d)
OH		hyperfine	H	Dagdigian (2022a)
OH		fine	ortho-H₂, para-H₂	Kłos et al. (2017)
OH⁺		hyperfine	electron	Hamilton et al. (2018)
OH⁺		hyperfine	H	Lique et al. (2016)
¹⁸OH⁺		hyperfine	H	Lique et al. (2016)
¹⁸OH⁺		hyperfine	electron	Hamilton et al. (2018)
CN		hyperfine	para-H₂	Kalugina et al. (2012)
CN		hyperfine	electron	Harrison et al. (2013)
¹³CN		hyperfine	para-H₂	Flower & Lique (2014)
C¹⁵N		hyperfine	para-H₂	Flower & Lique (2014)
CO		rotation	CO	Żółtowski et al. (2023)
CO		rotation	ortho-H₂O, para-H₂O	Faure et al. (2020)
CO		rotation	para-H₂	Chefdeville et al. (2015)
CO		rotation	ortho-H₂, para-H₂	Dagdigian (2022c)
¹³CO		rotation	ortho-H₂O, para-H₂O	Faure et al. (2020)
¹³CO		rotation	CO	Żółtowski et al. (2023)
¹³CO		rotation	ortho-H₂, para-H₂	Dagdigian (2022c)
¹³CO		rotation	para-H₂	Chefdeville et al. (2015)
C¹⁷O		hyperfine	ortho-H₂, para-H₂	Dagdigian (2022c)
¹³C¹⁷O		hyperfine	ortho-H₂, para-H₂	Dagdigian (2022c)
C¹⁸O		rotation	ortho-H₂O, para-H₂O	Faure et al. (2020)
C¹⁸O		rotation	ortho-H₂, para-H₂	Dagdigian (2022c)
C¹⁸O		rotation	CO	Żółtowski et al. (2023)
C¹⁸O		rotation	para-H₂	Chefdeville et al. (2015)
SH⁺		hyperfine	electron	Hamilton et al. (2018)
SH⁺		hyperfine	ortho-H₂, para-H₂	Dagdigian (2019)
SH⁺		hyperfine	H	Lique et al. (2020)
³⁶ArH⁺		rotation	H	Dagdigian (2018a)
³⁶ArH⁺		rotation	electron	Hamilton et al. (2015)
³⁸ArH⁺		rotation	electron	Hamilton et al. (2015)
³⁸ArH⁺		rotation	H	Dagdigian (2018a)
⁴⁰ArH⁺		rotation	H	Dagdigian (2018a)
⁴⁰ArH⁺		rotation	electron	Hamilton et al. (2015)
CS		rotation	electron	Varambhia et al. (2010)
CS		rotation	ortho-H₂, para-H₂	Denis-Alpizar et al. (2018)
SiO		rotation	electron	Varambhia et al. (2009)
SiO		rotation	ortho-H₂, para-H₂	Balança et al. (2018)
SO		fine	para-H₂	Lique et al. (2007)
NH₂	para	hyperfine	ortho-H₂, para-H₂	Bouhafs et al. (2019)
NH₂	ortho	hyperfine	ortho-H₂, para-H₂	Bouhafs et al. (2019)
H₂O	ortho	rotation	para-H₂	Daniel et al. (2011)
H₂O	ortho	rotation	ortho-H₂	Daniel et al. (2011)
H₂O	ortho	rotation	H	Daniel et al. (2014a)
H₂O	ortho	rotation	electron	Faure et al. (2004)
H₂O	para	rotation	para-H₂	Daniel et al. (2011)
H₂O	para	rotation	ortho-H₂	Daniel et al. (2011)
H₂O	para	rotation	H	Daniel et al. (2014a)
H₂O	para	rotation	electron	Faure et al. (2004)
HDO		rotation	ortho-H₂, para-H₂	Faure et al. (2024)
H¹⁸₂O	ortho	rotation	para-H₂	Daniel et al. (2011)
H¹⁸₂O	ortho	rotation	ortho-H₂	Daniel et al. (2011)
H¹⁸₂O	ortho	rotation	electron	Faure et al. (2004)
H¹⁸₂O	ortho	rotation	H	Daniel et al. (2014a)
H¹⁸₂O	para	rotation	para-H₂	Daniel et al. (2011)
H¹⁸₂O	para	rotation	ortho-H₂	Daniel et al. (2011)
H¹⁸₂O	para	rotation	electron	Faure et al. (2004)
H¹⁸₂O	para	rotation	H	Daniel et al. (2014a)
D₂O	ortho	rotation	ortho-H₂, para-H₂	Faure et al. (2024)
D₂O	para	rotation	ortho-H₂, para-H₂	Faure et al. (2024)
C₂H		hyperfine	ortho-H₂, para-H₂	Pirlot Jankowiak et al. (2023a)
C₂H		hyperfine	ortho-H₂, para-H₂	Dagdigian (2018b)
¹³CCH		hyperfine	para-H₂	Pirlot Jankowiak et al. (2023b)
C¹³CH		hyperfine	para-H₂	Pirlot Jankowiak et al. (2023b)
C₂D		hyperfine	ortho-H₂, para-H₂	Pirlot Jankowiak et al. (2023a)
HCN		rotation	He	Dumouchel et al. (2010)
HCN		rotation	electron	Faure et al. (2007)
HCN		rotation	ortho-H₂, para-H₂	Hernández Vera et al. (2017)
HCN		hyperfine	electron	Faure et al. (2007)
HCN		hyperfine	para-H₂	Magalhães et al. (2018)
HNC		rotation	electron	Faure et al. (2007)
HNC		rotation	ortho-H₂, para-H₂	Hernández Vera et al. (2017)
H¹³CN		rotation	para-H₂	Navarro-Almaida et al. (2023)
H¹³CN		rotation	He	Dumouchel et al. (2010)
H¹³CN		rotation	electron	Faure et al. (2007)
H¹³CN		hyperfine	para-H₂	Magalhães et al. (2018)
H¹³CN		rotation	ortho-H₂, para-H₂	Hernández Vera et al. (2017)
H¹³CN		hyperfine	electron	Faure et al. (2007)
HN¹³C		rotation	para-H₂	Navarro-Almaida et al. (2023)
HC¹⁵N		rotation	para-H₂	Navarro-Almaida et al. (2023)
HC¹⁵N		rotation	ortho-H₂, para-H₂	Hernández Vera et al. (2017)
HC¹⁵N		rotation	He	Dumouchel et al. (2010)
HC¹⁵N		rotation	electron	Faure et al. (2007)
DCN		hyperfine	electron	Faure et al. (2007)
DCN		hyperfine	para-H₂	Magalhães et al. (2018)
DCN		hyperfine	para-H₂	Giers et al. (2023)
DCN		rotation	electron	Faure et al. (2007)
DCN		rotation	ortho-H₂, para-H₂	Hernández Vera et al. (2017)
DCN		rotation	para-H₂	Navarro-Almaida et al. (2023)
DNC		rotation	para-H₂	Navarro-Almaida et al. (2023)
DNC		rotation	ortho-H₂, para-H₂	Hernández Vera et al. (2017)
DNC		rotation	electron	Faure et al. (2007)
HCO⁺		rotation	electron	Fuente et al. (2008)
HCO⁺		rotation	ortho-H₂, para-H₂	Denis-Alpizar et al. (2020)
N₂H⁺		hyperfine	para-H₂	Lique et al. (2015)
N₂H⁺		rotation	para-H₂	Balança et al. (2020)
D¹³CN		rotation	para-H₂	Navarro-Almaida et al. (2023)
H¹³CO⁺		rotation	electron	Fuente et al. (2008)
H¹³CO⁺		rotation	ortho-H₂, para-H₂	Denis-Alpizar et al. (2020)
N¹⁵NH⁺		hyperfine	para-H₂	Daniel et al. (2016a)
DCO⁺		rotation	electron	Fuente et al. (2008)
DCO⁺		rotation	para-H₂	Denis-Alpizar et al. (2020)
N₂D⁺		hyperfine	para-H₂	Lin et al. (2020)
H₂S	ortho	rotation	ortho-H₂, para-H₂	Dagdigian (2020)
H₂S	para	rotation	ortho-H₂, para-H₂	Dagdigian (2020)
HDS		rotation	ortho-H₂, para-H₂	Dagdigian (2022b)
H³⁴₂S	ortho	rotation	ortho-H₂, para-H₂	Dagdigian (2020)
H³⁴₂S	para	rotation	ortho-H₂, para-H₂	Dagdigian (2020)
D₂S	para	rotation	ortho-H₂, para-H₂	Dagdigian (2022b)
D₂S	ortho	rotation	ortho-H₂, para-H₂	Dagdigian (2022b)
HD³⁴S		rotation	ortho-H₂, para-H₂	Dagdigian (2022b)
SO₂		rotation	ortho-H₂, para-H₂	Cernicharo et al. (2011)
NH₃	para	rotation	ortho-H₂, para-H₂	Demes et al. (2023b)
NH₃	para	hyperfine	para-H₂	Loreau et al. (2023)
NH₃	para	rotation	H, ortho-H₂, para-H₂	Bouhafs et al. (2017)
NH₃	ortho	hyperfine	para-H₂	Loreau et al. (2023)
NH₃	ortho	rotation	H, ortho-H₂, para-H₂	Bouhafs et al. (2017)
NH₃	ortho	rotation	ortho-H₂, para-H₂	Demes et al. (2023b)
NH₂D	ortho	hyperfine	para-H₂	Daniel et al. (2016b)
NH₂D	para	hyperfine	para-H₂	Daniel et al. (2016b)
NH₂D	para	rotation	ortho-H₂, para-H₂	Daniel et al. (2014b)
NH₂D	ortho	rotation	ortho-H₂, para-H₂	Daniel et al. (2014b)
H₃O⁺	para	rotation	ortho-H₂, para-H₂	Demes et al. (2023a)
H₃O⁺	ortho	rotation	ortho-H₂, para-H₂	Demes et al. (2023a)
¹⁵NH₂D	para	rotation	ortho-H₂, para-H₂	Daniel et al. (2014b)
¹⁵NH₂D	ortho	rotation	ortho-H₂, para-H₂	Daniel et al. (2014b)
NHD₂	para	rotation	para-H₂	Daniel et al. (2016b)
NHD₂	para	hyperfine	para-H₂	Daniel et al. (2016b)
NHD₂	ortho	rotation	para-H₂	Daniel et al. (2016b)
NHD₂	ortho	hyperfine	para-H₂	Daniel et al. (2016b)
ND₃	ortho	rotation	para-H₂	Daniel et al. (2016b)
ND₃	ortho	hyperfine	para-H₂	Daniel et al. (2016b)
ND₃	para	rotation	para-H₂	Daniel et al. (2016b)
ND₃	meta	rotation	para-H₂	Daniel et al. (2016b)
ND₃	meta	hyperfine	para-H₂	Daniel et al. (2016b)
ND₃	para	hyperfine	para-H₂	Daniel et al. (2016b)
HCNH⁺		hyperfine	He, para-H₂	Bop et al. (2024)
HCNH⁺		rotation	He, para-H₂	Bop & Lique (2023)
HCNH⁺		rotation	ortho-H₂, para-H₂	Gong et al. (2025)
H₂CO	ortho	rotation	electron	Gerin et al. (2024)
H₂CO	ortho	rotation	ortho-H₂, para-H₂	Wiesenfeld & Faure (2013)
H₂CO	ortho	hyperfine	ortho-H₂, para-H₂	Troscompt et al. (2009)
H₂CO	ortho	hyperfine	electron	Gerin et al. (2024)
H₂CO	para	rotation	electron	Gerin et al. (2024)
H₂CO	para	rotation	ortho-H₂, para-H₂	Wiesenfeld & Faure (2013)
H¹³₂CO	para	rotation	ortho-H₂, para-H₂	Wiesenfeld & Faure (2013)
H¹³₂CO	ortho	rotation	ortho-H₂, para-H₂	Wiesenfeld & Faure (2013)
H₂C¹⁸O	ortho	rotation	ortho-H₂, para-H₂	Wiesenfeld & Faure (2013)
H₂C¹⁸O	para	rotation	ortho-H₂, para-H₂	Wiesenfeld & Faure (2013)
HOCO⁺		rotation	para-H₂	Dagdigian (2025)
CH₂NH		rotation	para-H₂	Faure et al. (2018)
CH₂NH		rotation	ortho-H₂, para-H₂	Xue et al. (2024)
CH₂NH		hyperfine	ortho-H₂, para-H₂	Xue et al. (2024)
CH₂NH		hyperfine	para-H₂	Faure et al. (2018)
c-C₃H₂	ortho	rotation	He, para-H₂	Ben Khalifa et al. (2019)
c-C₃H₂	para	rotation	He, para-H₂	Ben Khalifa et al. (2019)
l-C₃H₂	ortho	rotation	He, para-H₂	Ben Khalifa et al. (2019)
l-C₃H₂	para	rotation	He, para-H₂	Ben Khalifa et al. (2019)
c-¹³CC₂H₂	para	rotation	He, para-H₂	Ben Khalifa et al. (2019)
c-¹³CC₂H₂	ortho	rotation	He, para-H₂	Ben Khalifa et al. (2019)
HC₃N		hyperfine	ortho-H₂, para-H₂	Faure et al. (2016)
HC₃N		hyperfine	para-H₂	Hily-Blant et al. (2018)
HC₃N		rotation	electron	Gratier et al. (2013)
HC₃N		rotation	ortho-H₂, para-H₂	Faure et al. (2016)
HC₃N		rotation	para-H₂	Hily-Blant et al. (2018)
HNC₃		rotation	ortho-H₂, para-H₂	Bop et al. (2020)
HC¹⁵₃N		rotation	electron	Gratier et al. (2013)
HC¹⁵₃N		rotation	ortho-H₂, para-H₂	Faure et al. (2016)
HC¹⁵₃N		rotation	para-H₂	Hily-Blant et al. (2018)
CH₃OH	A	rotation	ortho-H₂, para-H₂	Dagdigian (2023)
CH₃OH	E	rotation	ortho-H₂, para-H₂	Rabli & Flower (2010)
CH₃OH	A	rotation	ortho-H₂, para-H₂	Rabli & Flower (2010)
CH₃OH	E	rotation	ortho-H₂, para-H₂	Dagdigian (2023)
CH₃OH	E	rotation	electron	Guzmán et al. (2013)
CH₃OH	A	rotation	electron	Guzmán et al. (2013)
¹³CH₃OH	E	rotation	ortho-H₂, para-H₂	Rabli & Flower (2010)
¹³CH₃OH	E	rotation	ortho-H₂, para-H₂	Dagdigian (2023)
¹³CH₃OH	A	rotation	ortho-H₂, para-H₂	Rabli & Flower (2010)
¹³CH₃OH	A	rotation	ortho-H₂, para-H₂	Dagdigian (2023)
CH¹₃⁸OH	A	rotation	ortho-H₂, para-H₂	Dagdigian (2023)
CH¹₃⁸OH	E	rotation	ortho-H₂, para-H₂	Dagdigian (2023)
CH¹₃⁸OH	A	rotation	ortho-H₂, para-H₂	Rabli & Flower (2010)
CH¹₃⁸OH	E	rotation	ortho-H₂, para-H₂	Rabli & Flower (2010)
CH₃CN	para	rotation	He, para-H₂	Ben Khalifa et al. (2023)
CH₃CN	ortho	rotation	He, para-H₂	Ben Khalifa et al. (2023)
CH₃NC	para	rotation	He, para-H₂	Ben Khalifa et al. (2023)
CH₃NC	ortho	rotation	He, para-H₂	Ben Khalifa et al. (2023)

Notes. Additional information such as the temperature ranges, energy level coverages, and various useful comments (such as isotopologue-specific or main isotopologue collisional data) can be found on the front page of each species at emaa.osug.fr. Note that in the case of molecules, the “fine” or “hyperfine” transition type means fine ors hyperfine transitions occuring within and between rotational levels.

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