Terpenylic acid and related compounds from the oxidation of alpha-pinene: implications for new particle formation and growth above forests.
Novel secondary organic aerosol (SOA) products from the monoterpene alpha-pinene with unique dimer-forming properties have been identified as lactone-containing terpenoic acids, i.e., terpenylic and 2-hydroxyterpenylic acid, and diaterpenylic acid acetate. The structural characterizations were based on the synthesis of reference compounds and detailed interpretation of mass spectral data. Terpenylic acid and diaterpenylic acid acetate are early oxidation products generated upon both photooxidation and ozonolysis, while 2-hydroxyterpenylic acid is an abundant SOA tracer in ambient fine aerosol that can be explained by further oxidation of terpenylic acid. Quantum chemical calculations support that noncovalent dimer formation involving double hydrogen bonding interactions between carboxyl groups of the monomers is energetically favorable. The molecular properties allow us to explain initial particle formation in laboratory chamber experiments and are suggested to play a role in new particle formation and growth above forests, a natural phenomenon that has fascinated scientists for more than a century.
Claeys
Magda
M
Department of Pharmaceutical Sciences, University of Antwerp, BE-2610 Antwerp, Belgium. magda.claeys@ua.ac.be
Iinuma
Yoshiteru
Y
Szmigielski
Rafal
R
Surratt
Jason D
JD
Blockhuys
Frank
F
Van Alsenoy
Christian
C
Böge
Olaf
O
Sierau
Berko
B
Gómez-González
Yadian
Y
Vermeylen
Reinhilde
R
Van der Veken
Pieter
P
Shahgholi
Mona
M
Chan
Arthur W H
AW
Herrmann
Hartmut
H
Seinfeld
John H
JH
Maenhaut
Willy
W
D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000737:chemistry; D000085:Acetates / Q000737:chemistry*; D000336:Aerosols / Q000032:analysis; D000081008:Bicyclic Monoterpenes; D002264:Carboxylic Acids / Q000737:chemistry*; D002853:Chromatography, Liquid; D019281:Dimerization; D005977:Glutarates; D006860:Hydrogen Bonding; D039821:Monoterpenes / Q000737:chemistry*; D010084:Oxidation-Reduction; D052638:Particulate Matter / Q000138:chemical synthesis*; D021241:Spectrometry, Mass, Electrospray Ionization; D014197:Trees / Q000737:chemistry*
D000085:Acetates; D000336:Aerosols; D000081008:Bicyclic Monoterpenes; D002264:Carboxylic Acids; D005977:Glutarates; D039821:Monoterpenes; D052638:Particulate Matter; C539247:diaterpenylic acid acetate; C544532:terpenylic acid; C005451:alpha-pinene; D015107:4-Butyrolactone