Infrared spectra of large acid hydrate clusters: formation conditions of submicron particles of nitric acid dihydrate and nitric acid trihydrate

1993 ◽  
Vol 97 (22) ◽  
pp. 5848-5851 ◽  
Author(s):  
Nancy Barton ◽  
Brad Rowland ◽  
J. Paul Devlin
Keyword(s):  
Nitric Acid ◽  
Infrared Spectra ◽  
Submicron Particles ◽  
Acid Hydrate ◽  
Formation Conditions

scholarly journals Variation of the infrared spectra of nitric acid hydrates with formation conditions: Impact on PSC identification

1999 ◽  
Vol 26 (6) ◽  
pp. 707-710 ◽  
Author(s):  
Robert T. Tisdale ◽  
Anthony J. Prenni ◽  
Laura T. Iraci ◽  
Margaret A. Tolbert ◽  
O. B. Toon
Keyword(s):  
Nitric Acid ◽  
Infrared Spectra ◽  
Formation Conditions

Observations on the Interpretation and Analysis of Sulfuric Acid Hydrate Infrared Spectra

2001 ◽  
Vol 105 (41) ◽  
pp. 9422-9426 ◽  
Author(s):  
Karen L. Nash ◽  
K. Jessica Sully ◽  
Andrew B. Horn
Keyword(s):  
Sulfuric Acid ◽  
Infrared Spectra ◽  
Acid Hydrate ◽  
Sulfuric Acid Hydrate

scholarly journals Homogeneous nucleation of NAD and NAT in liquid stratospheric aerosols: insufficient to explain denitrification

2002 ◽  
Vol 2 (3) ◽  
pp. 669-687 ◽  
Author(s):  
D. A. Knopf ◽  
T. Koop ◽  
B. P. Luo ◽  
U. G. Weers ◽  
T Peter
Keyword(s):  
Experimental Data ◽  
Nitric Acid ◽  
Nucleation Rate ◽  
Homogeneous Nucleation ◽  
Particle Production ◽  
Rate Coefficients ◽  
The Arctic ◽  
Linear Extrapolation ◽  
Acid Hydrate ◽  
Stratospheric Clouds

Abstract. The nucleation of NAD and NAT from HNO3/H2O and HNO3/H2O/H2SO4 solution droplets is investigated both theoretically and experimentally with respect to the formation of polar stratospheric clouds (PSCs). Our analysis shows that homogeneous NAD and NAT nucleation from liquid aerosols is insufficient to explain the number densities of large nitric acid containing particles recently observed in the Arctic stratosphere. This conclusion is based on new droplet freezing experiments employing optical microscopy combined with Raman spectroscopy. The homogeneous nucleation rate coefficients of NAD and NAT in liquid aerosols under polar stratospheric conditions derived from the experiments are < 2 x 10-5 cm-3 s-1 and < 8 x 10-2 cm-3 s-1 , respectively. These nucleation rate coefficients are smaller by orders of magnitude than the value of ~ 103 cm-3 s-1 used in a recent denitrification modelling study that is based on a linear extrapolation of laboratory nucleation data to stratospheric conditions (Tabazadeh et al., Science, 291, 2591--2594, 2001). We show that this linear extrapolation is in disagreement with thermodynamics and experimental data and, therefore, must not be used in microphysical models of PSCs. Our analysis of the experimental data yields maximum hourly production rates of nitric acid hydrate particles per cm3 of air of about 3 x 10-10 cm-3 h-1 under polar stratospheric conditions. Assuming PSC particle production to proceed at this rate for two months we arrive at particle number densities of < 5 x 10-7 cm-3, much smaller than the value of ~ 10-4 cm-3 reported in recent field observations. This clearly shows that homogeneous nucleation of NAD and NAT from liquid supercooled ternary solution aerosols cannot explain the observed polar denitrification.

Infrared spectra of solid films formed from vapors containing water and nitric acid

1991 ◽  
Vol 95 (15) ◽  
pp. 5924-5930 ◽  
Author(s):  
Roland H. Smith ◽  
Ming Taun Leu ◽  
Leon F. Keyser
Keyword(s):  
Nitric Acid ◽  
Infrared Spectra ◽  
Solid Films
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