\providecommand{\molref}[2]{\hyperref[#1]{\ce{#2}}}
\begin{table*}
\centering
\caption{List of molecules detected in external galaxies with references to the first detections.  Tentative detections are indicated, and some extra references are occasionally provided for context.}
\begin{tabular*}{\textwidth}{@{\extracolsep{\fill}} l l l l l l l l @{}}
\hline\hline
\multicolumn{2}{c}{\hyperref[2atoms]{2 Atoms}} & \multicolumn{2}{c}{\hyperref[3atoms]{3 Atoms}} & \multicolumn{2}{c}{\hyperref[4atoms]{4 Atoms}} & \multicolumn{2}{c}{\hyperref[5atoms]{5 Atoms}} \\
Species & Ref. & Species & Ref. & Species & Ref. & Species & Ref. \\
\hline
\molref{mol:CH}{CH}	&	1	&	\molref{mol:H2O}{H2O}	&	2	&	\molref{mol:NH3}{NH3}	&	3	&	\molref{mol:HC3N}{HC3N}	&	4, 5\\
\molref{mol:CN}{CN}	&	5	&	\molref{mol:HCO+}{HCO+}	&	6	&	\molref{mol:H2CO}{H2CO}	&	7	&	\molref{mol:HCOOH}{HCOOH}	&	8\\
\molref{mol:CH+}{CH+}	&	9	&	\molref{mol:HCN}{HCN}	&	10	&	\molref{mol:HNCO}{HNCO}	&	11	&	\molref{mol:CH2NH}{CH2NH}	&	12\\
\molref{mol:OH}{OH}	&	13	&	\molref{mol:OCS}{OCS}	&	14	&	\molref{mol:H2CS}{H2CS}	&	15	&	\molref{mol:NH2CN}{NH2CN}	&	15\\
\molref{mol:CO}{CO}	&	16	&	\molref{mol:HNC}{HNC}	&	5	&	\molref{mol:C2H2}{C2H2}	&	17	&	\molref{mol:H2CCO}{H2CCO}	&	12\\
\molref{mol:H2}{H2}	&	18	&	\molref{mol:H2S}{H2S}	&	19	&	\molref{mol:C3N}{C3N}	&	8	&	\molref{mol:C4H}{C4H}	&	12\\
\molref{mol:SiO}{SiO}	&	20	&	\molref{mol:N2H+}{N2H+}	&	20	&	\molref{mol:HOCO+}{HOCO+}	&	21, 15	&	\molref{mol:c-C3H2}{c-C3H2}	&	22\\
\molref{mol:CS}{CS}	&	23	&	\molref{mol:C2H}{C2H}	&	5	&	\molref{mol:l-C3H}{l-C3H}	&	12	&	\molref{mol:CH2CN}{CH2CN}	&	12\\
\molref{mol:SO}{SO}	&	24, 25	&	\molref{mol:SO2}{SO2}	&	26	&	\molref{mol:H3O+}{H3O+}	&	27	&	\molref{mol:H2CCC}{H2CCC}	&	12\\
\molref{mol:NS}{NS}	&	26	&	\molref{mol:HCO}{HCO}	&	28, 29	&	\molref{mol:c-C3H}{c-C3H}$^{\dagger}$	&	15	&		&	\\
\molref{mol:C2}{C2}	&	30	&	\molref{mol:HCS+}{HCS+}	&	31	&	\molref{mol:H2CN}{H2CN}	&	8	&		&	\\
\molref{mol:NO}{NO}	&	26	&	\molref{mol:HOC+}{HOC+}	&	32	&	\molref{mol:HOCN}{HOCN}	&	33	&		&	\\
\molref{mol:HCl}{HCl}	&	34	&	\molref{mol:C2S}{C2S}	&	15	&	\molref{mol:l-C3H+}{l-C3H+}	&	8	&		&	\\
\molref{mol:PN}{PN}	&	35	&	\molref{mol:C3}{C3}	&	30	&	\molref{mol:H2NC}{H2NC}	&	36	&		&	\\
\molref{mol:NH}{NH}	&	37	&	\molref{mol:NH2}{NH2}	&	38	&		&		&		&	\\
\molref{mol:SO+}{SO+}	&	12	&	\molref{mol:H3+}{H3+}	&	39	&		&		&		&	\\
\molref{mol:CO+}{CO+}	&	40	&	\molref{mol:H2O+}{H2O+}	&	41	&		&		&		&	\\
\molref{mol:HF}{HF}	&	42, 43, 44	&	\molref{mol:H2Cl+}{H2Cl+}	&	45	&		&		&		&	\\
\molref{mol:CF+}{CF+}	&	46	&		&		&		&		&		&	\\
\molref{mol:O2}{O2}	&	47	&		&		&		&		&		&	\\
\molref{mol:OH+}{OH+}	&	42, 43, 48	&		&		&		&		&		&	\\
\molref{mol:SH+}{SH+}	&	49	&		&		&		&		&		&	\\
\molref{mol:ArH+}{ArH+}	&	50	&		&		&		&		&		&	\\
\hline\hline
\end{tabular*}
\begin{tabular*}{\textwidth}{@{\extracolsep{\fill}} l l l l l l l l l l @{}}
\multicolumn{2}{c}{\hyperref[6atoms]{6 Atoms}} & \multicolumn{2}{c}{\hyperref[7atoms]{7 Atoms}} & \multicolumn{2}{c}{\hyperref[8atoms]{8 Atoms}} & \multicolumn{2}{c}{\hyperref[9atoms]{9 Atoms}} & \multicolumn{2}{c}{\hyperref[12atoms]{12 Atoms}} \\
Species & Ref. & Species & Ref. & Species & Ref. & Species & Ref. & Species & Ref. \\
\hline
\molref{mol:CH3OH}{CH3OH}	&	51	&	\molref{mol:CH3CHO}{CH3CHO}	&	12	&	\molref{mol:HCOOCH3}{HCOOCH3}	&	52	&	\molref{mol:CH3OCH3}{CH3OCH3}	&	53, 52	&	\molref{mol:C6H6}{C6H6}	&	54\\
\molref{mol:CH3CN}{CH3CN}	&	55	&	\molref{mol:CH3CCH}{CH3CCH}	&	55	&	\molref{mol:HC6H}{HC6H}	&	54	&	\molref{mol:CH3CH2OH}{CH3CH2OH}	&	33	&		&	\\
\molref{mol:NH2CHO}{NH2CHO}	&	31	&	\molref{mol:CH3NH2}{CH3NH2}	&	12	&		&		&		&		&		&	\\
\molref{mol:CH3SH}{CH3SH}	&	8	&	\molref{mol:CH2CHCN}{CH2CHCN}	&	8	&		&		&		&		&		&	\\
\molref{mol:HC2CHO}{HC2CHO}	&	33	&	\molref{mol:HC5N}{HC5N}$^{\dagger}$	&	21	&		&		&		&		&		&	\\
\molref{mol:HC4H}{HC4H}	&	54	&		&		&		&		&		&		&		&	\\
\hline
\end{tabular*}
\justify
$^{\dagger}$Tentative detection\\
\textbf{References:} [1] \citet{Whiteoak:1980:17P} [2] \citet{Churchwell:1977:969} [3] \citet{Martin:1979:L7} [4] \citet{Mauersberger:1990:63} [5] \citet{Henkel:1988:L23} [6] \citet{Stark:1979:118} [7] \citet{Gardner:1974:526} [8] \citet{Tercero:2020:L7} [9] \citet{Magain:1987:L5} [10] \citet{Rickard:1977:390} [11] \citet{Nguyen-Q-Rieu:1991:L33} [12] \citet{Muller:2011:A103} [13] \citet{Weliachew:1971:L47} [14] \citet{Mauersberger:1995:23} [15] \citet{Martin:2006:450} [16] \citet{Rickard:1975:L75} [17] \citet{Matsuura:2002:L133} [18] \citet{Thompson:1978:L49} [19] \citet{Heikkila:1999:817} [20] \citet{Mauersberger:1991:457} [21] \citet{Aladro:2015:A101} [22] \citet{Seaquist:1986:L67} [23] \citet{Henkel:1985:L25} [24] \citet{Johansson:1991:1} [25] \citet{Petuchowski:1992:137} [26] \citet{Martin:2003:L465} [27] \citet{vanderTak:2008:L5} [28] \citet{Sage:1995:625} [29] \citet{Garcia-Burillo:2002:L55} [30] \citet{Welty:2013:1107} [31] \citet{Muller:2013:A109} [32] \citet{Usero:2004:897} [33] \citet{Martin:2021:A46} [34] \citet{Wallstrom:2019:A128} [35] \citet{Haasler:2022:A158} [36] \citet{Cabezas:2021:A45} [37] \citet{Gonzalez-Alfonso:2004:247} [38] \citet{Muller:2014:A112} [39] \citet{Geballe:2006:907} [40] \citet{Fuente:2006:L105} [41] \citet{Weiss:2010:L1} [42] \citet{vanderWerf:2010:L42} [43] \citet{Rangwala:2011:94} [44] \citet{Monje:2011:L21} [45] \citet{Muller:2014:L6} [46] \citet{Muller:2016:L5} [47] \citet{Wang:2020:129} [48] \citet{Gonzalez-Alfonso:2013:A25} [49] \citet{Muller:2017:A109} [50] \citet{Muller:2015:L4} [51] \citet{Henkel:1987:L1} [52] \citet{Sewilo:2018:L19} [53] \citet{Qiu:2018:A3} [54] \citet{Bernard-Salas:2006:L29} [55] \citet{Mauersberger:1991:307}\\
\label{exgal_mols}
\end{table*}\endinput