10 mm High-Resolution Spectra of Acrolein trans-structure assignments for n14 and n16 groups .


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Acrolein H2C=C(H)- C(H)=O Cs symmetry. . . . cis-formEelec. = - 191.9707933 (Hartree). trans-formEelec. = - 191.9742621 (Hartree). 1 Hartree = 219474 cm-1. In view of stomach muscle initio figuring at B3LYP/6-311 G** utilizing Gaussian03. DEele ~ 760 cm-1. . . Presentation - ecological and wellbeing concerns.
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Slide 1

10 m High-Resolution Spectra of Acrolein ( trans - frame) assignments for n 14 and n 16 groups H 2 C=C(H)- C(H)=O (C S ) Objective - to give benchmark high-determination research facility information in the 10 m district for smoke recognition X.J. Jiang, J.M. Fisher, Li-Hong Xu Center for Laser, Atomic and Molecular Sciences (CLAMS), Dept of Physical Sciences, Univ. of New Brunswick, Saint John, NB, Canada A.R.W. McKellar Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Canada

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Acrolein H 2 C=C(H)- C(H)=O C s symmetry trans - shape E elec. = - 191.9742621 (Hartree) cis - frame E elec. = - 191.9707933 (Hartree) D E ele ~ 760 cm - 1 Hartree = 219474 cm - 1 Based on stomach muscle initio computation at B3LYP/6-311++G** utilizing Gaussian03

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Introduction - e nvironmental and wellbeing concerns Acrolein assumes an essential part in contamination and is recorded in US-EPA 188 H azardous An ir P ollutants (HAPs) It is one of the need versatile air toxics ( Acetaldehyde, Acrolein, Benzene, 1,3-Butadiene, Formaldehyde, Diesel Particulate Matter + Diesel Exhaust Organic Gas Source: J. Wilson, FHWA Air Toxics Workshop, Chicago, IL, May 12, 2003 It is basically utilized as a synthetic middle of the road in the generation of acrylic corrosive and its esters Combustion of fossil powers and tobacco smoke add to the natural predominance of acrolein

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GC MS-MS Proton Transfer MS FTIR (low determination IR) Open way air P T not able I nfrared L aser D ifferential A bsorption S pectroscopy (TILDAS) Extractive inspecting, low P Continuous High Speed < 1 s High Resolution High Sensitivity Absolute Concentrations Sub-List of HAPs Most Applicable to TILDAS Detection Methods -Acetaldehyde * -Acrolein * -Acrylonitrile -1-3 Butadiene * -Benzene -Carbonyl Sulfide -Ethylene Oxide -Formaldehyde -Formic Acid -Hydrazine -Methanol * * as of now focused on atoms H azardous An ir P ollutants (HAP) Detection Methods Aerodyne Research, Inc. & Philip Morris Research Center, VA. High determination information are required, and are not yet accessible in writing

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Vibrational methods of acrolein ( trans - shape) A\' Description Obs (cm - 1 ) n 1 =CH 2 a-str 3103 n 2 CH* str 3069 n 3 =CH 2 s-str 2998 n 4 CH** str 2800 n 5 C=O str 1742 n 6 C=C str 1625 n 7 =CH 2 sci 1420 n 8 CH** bend 1360 A" Description Obs (cm - 1 ) n 9 CH* bend 1275 n 14 =CH 2 twist 993 n 10 C-C str 1158 n 15 CH** o/p 972 n 11 =CH 2 i/p 912 n 16 =CH 2 o/p 959 n 12 CCO bend 564 n 17 CH* o/p 593 n 13 CCC bend 324 n 18 C-C tor 158 Vib. degrees of flexibility: 3x8 - 3T - 3R = 18 * ** Ref. Y. Hamada, Y. Nishimura, M. Tsuboi, Chem. Phys. 100 (1985) 365-375.

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Survey range of Acrolein - Pacific Northwest National Laboratory

Slide 7

Acrolein ( trans - shape): High Resolution Spectroscopy Low vitality trans - frame has been examined widely by microwave spectroscopy; No past high-determination considers exist for the 10 m district; High-determination FTIR spectra have been recorded at the National Research Council of Canada from 800 – 1100 cm - 1 @ 0.002 cm - 1 determination at room and cooled temp. Range I: 295K, 30 cm multi-pass cell set to 4 travels, ~500 mTorr Spectrum II: 180K, 2 m multi-pass cell set to 4 travels, ~60 mTorr cover at any rate the n 11 (A\' CH 2 shaking, in-plane), 912 cm - 1 n 16 (A" CH 2 swaying, out-of-plane) 959 cm - 1 n 14 (A" CH 2 twisting) 993 cm - 1 Rotational investigations of the n 16 and n 14 groups – both c-sorts are accounted for here.

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Acrolein – Low Resolution Plot – n 11 , n 16 , n 14 modes Room Temp. q n 16 A" c-sort CH 2 swaying o/p n 14 A" c-sort CH 2 curving n 11 A\' b-sort CH 2 shaking i/p r Q Ka" ® ¬ p Q Ka" r Q Ka" ® ¬ p Q Ka"

Slide 9

Acrolein – Medium Resolution Plot – n 14 & n 16 Bands n 14 CH 2 bending n 16 CH 2 shaking o/p r Q Ka" p Q Ka" r Q Ka" p Q Ka" n 16 K a " 2 3 4 5 6 7 8 9 n 14 K a " 1 2 3 4 5 6 7 9 8 7 6 5 4 3 r Q of n 16 and p Q of n 14 cover to some degree

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¬ n 3 4 P 16 ¬ n 4 5 P 16 ¬ n 5 6 P 16 ¬ n 3 4 P 14 ¬ n 5 6 P 14 ¬ n 4 3 R 16 ¬ n 5 4 R 16 ¬ n 3 2 R 16 High Resolution Display P25 P23 P24 P17 P16 P15 P14 n 16 P P8 P7 P6 941.0 941.1 941.2 941.3 941.4 941.5 941.6 941.7 941.8 941.9 942.0 942.1 n 14 P P27 P26 P29 P28 P6 P9 P8 P7 n 16 6 ¬ 5 Q n 16 2 ¬ 1 R27 1,27 R16 R17 R19 R18 R8 R6 R7 R9 n 16 R R26 R27 R25 974.0 974.1 974.2 974.3 974.4 974.5 974.6 974.7 974.8 974.9 975.0 975.1 Wavenumber (cm - 1 )

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Modeling – Watson Asymmetric Rotor Hamiltonian (disengaged band approach) n 18 (ground state): - 270 MW moves were beforehand measured in the writing. - They were refitted for refined ground state parameters. n 16 (A "" CH 2 out-of-plane swaying): - Upper states have been recognized for K a " = 0 to 10 . - Small asymmetry splittings for K a " < 5 have been watched . - The band has been demonstrated by a Watson hilter kilter rotor Hamiltonian with K a " = 7 and 8 barred . n 14 (A "" CH 2 winding): - Upper states have been distinguished for K a " = 1 to 9 . - Small asymmetry splittings for K a " < 5 have been watched . - The band has been displayed by a Watson lopsided rotor Hamiltonian with K a " = 1-3 avoided .

Slide 12

Molecular Parameters Ground State a n 16 (CH 2 swaying) n 14 (CH 2 turning) n vib 0.0 958.74075(11) 992.65739(69) A 1.57954994(15) 1.596714(10) 1.570188(54) B 0.1554241692(67) 0.15529624(80) 0.155220(16) C 0.1415208986(73) 0.14152245(82) 0.141938(19) D K x10 5 1.2023(16) 2.506(26) 0.76(13) D J K x10 6 - 0.292890(96) -0.286(13) 1.058(63) D J x10 7 0.34750(12) 0.3543(31) d J x10 8 0.39988(35) 0.458(30) d K x10 5 0.0193(89) 0.1026(76) - 1.000(19) H K x10 7 -0.137(19) -0.385(95) H KJ x10 8 - 0.001594(34) -0.571(10) 1.688(50) H JK x10 10 - 0.0029(18) -0.146(69) # of lines 270 962 (K a " =7,8 prohibited) 552 (K a " =1-3 avoided) RMS 0.017 MHz 0.0010 cm - 1 0.0013 cm - 1 a Ground state parameters have been changed over to cm - 1 for prepared correlation.

Slide 13

J - Reduced Energy Diagram n 16 Ka 10 9 8 7 6 5 4 3 2 1/0 (cm - 1 ) n 14 Ka 9 8 7 6 5 4 3 2 1 J values

Slide 14

Summary and Future To a substantial degree, the n 16 (A " ) c-sort CH 2 out-of-plane swaying band (959 cm - 1 ) and n 14 (A " ) c - sort CH 2 curving band (993 cm - 1 ) can be demonstrated by a Watson awry rotor Hamiltonian, treating each state independently with some subbands barred (we trust states avoided are annoyed); We plan to do examination for the n 11 (A\') CH 2 in-plane shaking mode (912 cm - 1 ) next, as state communications are normal between n 11 , n 16 and n 14 . Without a doubt, we have watched some unpredictable J and K designs in n 16 and n 14 . Keeping in mind the end goal to treat the spectra legitimately, it may be useful to utilize a communicating band show; We have recently begun to demonstrate the n 14 and n 16 states at the same time with consideration of symmetry permitted terms between the n 14 and n 16 . In future, additionally low temp FTIR spectra would be truly useful with the new Bruker IFS125 HR FTS (0.0009 cm - 1 unapodized max. res.) at the Canadian Light Source in Saskatoon. Affirmations: money related support from NSERC; on account of Dr. M.S. Zahniser at Aerodyne Research, Inc., for raising this intriguing subject of study.

Slide 15

Line Intensity Calculation Ab initio Dipole Derivative Calculation e : Nuclear turn factual weight n ij : Transition recurrence  : Loschmidt\'s number T : Temperature Z : Partition capacities (vib, tors,rot) |< m >| 2 : Transition minute - vibrational A : Honl-London figure – decay. cover Structure & recurrence estimation with Gaussian 03 at B3LYP/6-311++G** - Eigenvectors (removals) for every ordinary mode (standard introduction, standardized, not orthogonal): increased by (m rd_n ) 1/2 Þ PAM - Dipole subsidiary (in z-grid introduction) Þ PAM - Dipole subsidiaries for every typical mode in PAM framework (n = 1 to 3N-6) (g = x, y, z)

Slide 16

Vibrational methods of acrolein ( trans - shape) A\' Description Obs (cm - 1 ) n 1 =CH 2 a-str 3103 n 2 CH* str 3069 n 3 =CH 2 s-str 2998 n 4 CH** str 2800 n 5 C=O str 1742 n 6 C=C str 1625 n 7 =CH 2 sci 1420 n 8 CH** bend 1360 A" Description Obs (cm - 1 ) n 9 CH* bend 1275 n 14 =CH 2 twist 993 n 10 C-C str 1158 n 15 CH** o/p 972 n 11 =CH 2 i/p 912 n 16 =CH 2 o/p 959 n 12 CCO bend 564 n 17 CH* o/p 593 n 13 CCC bend 324 n 18 C-C tor 158 High-determination FTIR spectra have additionally been recorded at NRC in FIR area Convering: Low recurrence vibrations and n 18 hot band Analysis is in advance - A.R.W. McKellar NRC Ref. Y. Hamada, Y. Nishimura, M. Tsuboi, Chem. Phys. 100 (1985) 365-375.

Slide 17

10 m High-Resolution Spectra of 1,3-Butadiene H 2 C=C(H)- C(H)=CH 2 (C 2h ) Acrolein H 2 C=C(H)- C(H)=O (C S ) Objective - to give and develop benchmark high-determination lab information for the two particles in the 10 m district Li-Hong Xu, X.J. Jiang, J. Fisher, Z.D. Sun, R.M. Remains Center for Laser, Atomic and Molecular Sciences (CLAMS), Dept of Physical Sciences, Univ. of New Brunswick, Saint John, NB, Canada N.C. Craig A.R.W. McKellar Dept. of Chemistry, Steacie Institute for Molecular Sciences, Oberlin College, National Research Cou

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