Millimeter/Submillimeter Spectroscopy of Prebiotic Molecules Formed from the O( 1 D) Insertion Into Methylamine Brian Hays, Althea Roy, and Susanna Widicus Weaver Emory University

H 2 O + h OH + H H 2 + O CH 3 OH + h CH 3 + OH CH 3 O + H CH 2 OH + H NH 3 + h NH 2 + H h H 2 O, CO, CH 3 OH, NH 3, H 2 CO Ice mantle Complex Chemistry in the ISM Garrod, Widicus Weaver, & Herbst, 2008 Charnley, 2001

H 2 O + h OH + H H 2 + O CH 3 OH + h CH 3 + OH CH 3 O + H CH 2 OH + H NH 3 + h NH 2 + H CH 2 OH + NH 2 HOCH 2 NH 2 Aminomethanol h H 2 O, CO, CH 3 OH, NH 3, H 2 CO Ice mantle Complex Chemistry in the ISM Garrod, Widicus Weaver, & Herbst, 2008 Charnley, 2001

H 2 O + h OH + H H 2 + O CH 3 OH + h CH 3 + OH CH 3 O + H CH 2 OH + H NH 3 + h NH 2 + H h H 2 O, CO, CH 3 OH, NH 3, H 2 CO Ice mantle Complex Chemistry in the ISM CH 2 OH + NH 2 HOCH 2 NH 2 Aminomethanol Garrod, Widicus Weaver, & Herbst, 2008 Charnley, 2001

Proposed Formation Route for Laboratory Spectroscopy Molecules reactive under terrestrial conditions so no laboratory spectra exist

Proposed Formation Route for Laboratory Spectroscopy Molecules reactive under terrestrial conditions so no laboratory spectra exist Molecules can be produced using barrierless O( 1 D) insertion reactions O( 1 D) primarily inserts into bonds that are H-X where X=C, N, O, H eV energy E O( 1 D) O( 3 P)

O( 1 D) Insertion Into Methane Chang and Lin, Chem. Phys. Lett. 363 (2002) H

Gas-Phase O( 1 D) Insertion Reactions Microwave Synthesizer Millimeter/Submillimeter Frequency Multiplier 50 GHz – 1.2 THz Hot Electron Bolometer Excimer Laser Pulsed Valve + Fused Silica Capillary O 3 + hν (248 nm)  O 2 ( 1 Δ) + O( 1 D) O( 1 D) + Precursor  Product Oscilloscope Supersonic Expansion Ar, CH 4, O 2, O 3

Ozone Depletion O 3 + hν (248 nm)  O 2 ( 1 Δ) + O( 1 D)

Methanol Production O( 1 D) + CH 4  CH 3 OH _

Methanol from O( 1 D) Insertion First detection of O( 1 D) insertion products with a supersonic expansion First millimeter/submillimeter spectrometer that probes laser- induced bimolecular reaction products in a supersonic expansion Also detected: H 2 CO, HO 2, CH 3 O

Methylamine Reaction Hays & Widicus Weaver 2013, JPCA, 117, 7142 CCSD(T)//MP2/aug-cc-pVTZ

Methylamine Reaction CH 3 NH 2 + O 3  ????? Significant dark reactions behind pulsed valve Reduces ozone concentration before photolysis Chokes valve

Methylamine Reaction Gases are mixed immediately before the photolysis region Dark reactions between precursor gases are minimized Valves are more stable because side products cannot form in gas line O3O3 CH 3 NH 2 CH 3 NH 2 + O 3  ?????

Methylamine Reaction O( 1 D) + CH 3 NH 2  products Laser RFI Depletion

Methylamine + O( 1 D) Reactions CH 3 NH 2 + O( 1 D) → HOCH 2 NH 2 (aminomethanol) CH 3 NHOH (n-methyl hydroxylamine) CH 3 ONH 2 (aminomethyl ether) Known molecules that have been detected: CH 3 OH, H 2 CO, CH 3 O, HO 2, NO, CH 2 NH, NH 2 CHO HNCO, HCNO, HNO HCN, HNC, HOOH HONO, H 2 CN(?) Possible products requiring other frequency windows: NH 3, H 2 O, OH Methylenimine CH 2 NH J Ka,Kc = 1 1,0 – 1 0,1 F=0–1 2–1 1–2 F=2–2 1–0 1–1

Several unknown transitions have been found Some are close to predicted H 2 CN transitions but no previously observed H 2 CN transitions have been found Guided by ab initio calculations Towards detection of aminomethanol

Hyperfine splitting indicates an N-containing molecule Frequency does not match for any known N-containing products Near calculated ZPE corrected predicted lines, but … Toward detection of aminomethanol

Line intensities increase with increased methylamine conc. As these lines increase, lines from other secondary products (i.e., formaldehyde, methanol) decrease Evidence indicates that these lines arise from a primary insertion product Toward detection of aminomethanol

Several more lines detected around several predicted cold aminomethanol transitions that don’t match any catalog spectra Toward detection of aminomethanol

Conclusions and Future Work O( 1 D) insertion reactions are efficient for forming astrochemical target molecules Methane experiments demonstrate efficiency of O( 1 D) insertion mechanism Methylamine experiments give a wide variety of products Once confirmed, aminomethanol spectra will be compared with 32 CSO spectral line surveys

Conclusions and Future Work O( 1 D) insertion reactions are efficient for forming astrochemical target molecules Methane experiments demonstrate efficiency of O( 1 D) insertion mechanism Methylamine experiments give a wide variety of products Once confirmed, aminomethanol spectra will be compared with 32 CSO spectral line surveys Nadine Wehres - RF10, Thursday afternoon ALMA session

Acknowledgements Widicus Weaver group – Nadine Wehres, Jake Laas, Bridget Deprince Dr. Michael Heaven for loan of laser and ozone generator Sven Thorwirth Cherry L. Emerson Emory for calculations NSF #CHE NASA #NNX11AI07G