Browsing by Author "Chou, Sheng-Lung"

Now showing 1 - 5 of 5

FORMATION AND IDENTIFICATION OF INTERSTELLAR MOLECULE LINEAR C(5)H FROM PHOTOLYSIS OF METHANE DISPERSED IN SOLID NEON
(2009-08-10)
Wu, Yu-Jong
;
Chen, Hui-Fen
;
Camacho, Cristopher
;
Witek, Henryk A.
;
Hsu, Sheng-Chuan
Photolysis of methane dispersed (1/1000) in solid Ne at 3 K with vacuum-ultraviolet light from a synchrotron produced infrared absorption lines of several products, including new lines at 3319.3 and 1955.5 cm(-1). Based on experiments with isotopic labeling and results of quantum-chemical calculations, these lines are assigned to the C-H stretching and C=C stretching modes, respectively, of interstellar molecule linear C(5)H radicals.
FORMATION AND IDENTIFICATION OF INTERSTELLAR MOLECULE LINEAR C5H FROM PHOTOLYSIS OF METHANE DISPERSED IN SOLID NEON
(2009-08-10)
Wu, Yu-Jong
;
Chen, Hui-Fen
;
Camacho, Cristopher
;
Witek, Henryk A.
;
Hsu, Sheng-Chuan
Photolysis of methane dispersed (1/1000) in solid Ne at 3 K with vacuum-ultraviolet light from a synchrotron produced infrared absorption lines of several products, including new lines at 3319.3 and 1955.5 cm(-1). Based on experiments with isotopic labeling and results of quantum-chemical calculations, these lines are assigned to the C-H stretching and C=C stretching modes, respectively, of interstellar molecule linear C5H radicals.
Formation and infrared spectra of monohydrogenated pyrenes 2-C16H11 and 4-C16H11 trapped in solid para-hydrogen
(2020-06-05)
Bahou, Mohammed
;
Chou, Sheng-Lung
;
Wu, Yu-Jong
;
應用化學系
;
應用化學系分子科學碩博班
We recorded the IR spectra of 2-C16R11 and 4-C16R11 trapped in solid para-hydrogen (p-H-2). These species were produced on the electron bombardment of p-H-2 containing pyrene (C16H10) in a small proportion during matrix deposition. IR absorption features of 1-C16H11+ and 1-C16H11 in solid p-H-2 were previously identified [J. Phys. Chem. Lett. 4 (2013) 1989]. Here, the irradiation of a similar matrix sample at 365 nm depleted 1-C(16)H(11)(+ )and 2-C16H11 and produced 1-C16H11 and 4-C16H11. In contrast, irradiation at 405 nm decreased 1-C16H11+, 2-C16H11 and 4-C16H11. The identification of the observed lines of 2-C16H11, and 4-C16H11 was supported by predictions of the vibrational wavenumbers and relative IR intensities at the B3PW91/6-311++G(2d,2p) level of theory. (C) 2020 Elsevier B.V. All rights reserved.
Formation and IR spectrum of monobridged Si2H4 isolated in solid argon
(2020-05-29)
Lin, Shu-Yu
;
Chou, Sheng-Lung
;
Lin, Meng-Yeh
;
Huang, Wen-Jian
;
Huang, Tzu-Ping
The infrared (IR) spectrum of monobridged Si2H4 (denoted as mbr-Si2H4) isolated in solid Ar was recorded, and a set of lines (in the major matrix site) observed at 858.3 cm(-1), 971.5 cm(-1), 999.2 cm(-1), 1572.7 cm(-1), 2017.7 cm(-1), 2150.4 cm(-1), and 2158.4 cm(-1) were characterized. The species was produced by the electron bombardment of an Ar matrix sample containing a small proportion of SiH4 during matrix deposition. Upon photolysis of the matrix samples using 365 nm and 160 nm light, the content of mbr-Si2H4 increased. The band positions, relative intensity ratios, and D-isotopic shift ratios of the observed IR features are generally in good agreement with those predicted by the B3LYP/aug-cc-pVTZ method. In addition, the photochemistry of the observed products was discussed.
Vacuum ultraviolet photolysis of CH4:O-2 ice mixtures and the formation of CO and CO2
(2020-06-05)
Chou, Sheng-Lung
;
Lin, Meng-Yeh
;
Huang, Tzu-Ping
;
Wu, Yu-Jong
;
應用化學系
Vacuum ultraviolet (VUV) photolysis of CH4:O-2 ice mixtures at 10 K using 121.6, 157, and 170-nm wavelengths was performed to examine photochemical reactions for the oxidation of hydrocarbon species. Ice samples with three component ratios were prepared: CH4-dominated (CH4:O-2 = 100:1), mixed (CH4:O-2 = 1:1), and O-2-dominated (CH4:O-2 = 1:100) ice samples. Photochemical behavior with dependence on the photolysis wavelength and component ratio was observed. In addition, the column densities of CO and CO2 formed by the VUV photolysis of the three ice samples and the abundance ratios of CO and CO2 as a function of the photon dosage and photolysis wavelength were examined. The results may imply a correlation between the unknown depletion of interstellar oxygen and the formation of CO and CO2. (C) 2020 Elsevier B.V. All rights reserved.