Time-Resolved FT-IR Absorption Spectroscopy Using a Step-Scan Interferometer

Ten-nanosecond time resolution has been achieved with step-scan FT-IR absorbance difference spectroscopy (S2FT-IR Δ A TRS) and demonstrated by measuring Δ A spectra of fac-[Re(bpy)(CO)3Cl] and cis-[Os(bpy)2(CO)(4,4′-bpy)]2+ (bpy = 2,2′-bipyridine; 4,4′-bpy=4,4′-bipyridine) in CH3CN solution, following 355-nm laser excitation. In both complexes, the large shifts in (CO) to higher energy are consistent with the assignment that the lowest-energy excited states are metal-to-ligand charge transfer in nature. For [Os(bpy)2(CO)(4,4′-bpy)]2+, it is also possible to measure the excited-state decay kinetics, again with 10-ns resolution. In addition, Δ A bands are observed that are related to excited-state vibrations of the bipyridine ligands. Δ A spectra of good signal-to-noise ratio can be obtained for complexes with lifetimes as short as 10 ns.

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FT-IR absorption spectroscopy of BEDT-TTF radical salts: charge transfer and donor-anion interaction

Synthetic Metals ◽

10.1016/0379-6779(93)91180-a ◽

1993 ◽

Vol 60 (1) ◽

pp. 31-38 ◽

Cited By ~ 53

Author(s):

J. Moldenhauer ◽

Ch. Horn ◽

K.I. Pokhodnia ◽

D. Schweitzer ◽

I. Heinen ◽

...

Keyword(s):

Charge Transfer ◽

Absorption Spectroscopy ◽

Ir Absorption ◽

Ft Ir ◽

Anion Interaction

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Ultra-Fast Potential Jump at the Electrochemical Interface Studied by Picosecond Time-Resolved Surface-Enhanced IR Absorption Spectroscopy

ECS Meeting Abstracts ◽

10.1149/ma2006-02/44/1915 ◽

2006 ◽

Keyword(s):

Absorption Spectroscopy ◽

Ir Absorption ◽

Potential Jump ◽

Time Resolved ◽

Surface Enhanced ◽

Electrochemical Interface

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Application of FT-IR Absorption Spectroscopy for in Situ Gas Concentration and Temperature Measurements in Laboratory- and Pilot-Scale Combustion Environments

Applied Spectroscopy ◽

10.1366/0003702934066046 ◽

1993 ◽

Vol 47 (11) ◽

pp. 1898-1906 ◽

Cited By ~ 11

Author(s):

Denise M. Martin ◽

Patrick J. Medvecz ◽

Kenneth M. Nichols

Keyword(s):

Gas Phase ◽

Absorption Spectra ◽

Absorption Spectroscopy ◽

Diagnostic Tool ◽

Heterogeneous Reaction ◽

Black Liquor ◽

Pilot Scale ◽

Ir Absorption ◽

Ft Ir

In situ FT-IR absorption spectroscopy was used as a diagnostic tool to evaluate the gas phase above a heterogeneous reaction, black liquor char combustion. Previously developed calculation methodologies were used to determine the CO and CO2 concentrations and the CO rotational temperatures from absorption spectra. Spectroscopically obtained gas temperatures and concentrations from laboratory-scale experiments were compared to thermocouple and NDIR measurements. Quantitative evaluations of the gas phase during these experiments indicated that gas temperatures can be measured with an accuracy of 2–3% at 450–750 K and gas concentrations can be measured with accuracies of better than 10% at gas concentrations between 0.3 and 1.3%. Gas temperatures obtained during pilot-scale combustion were between 1118 and 1183 K, while concentrations were between 0.35 and 0.76%. Differences among gas concentrations and temperatures calculated from the absorption spectra, compared to NDIR measurements and thermocouples, were greater than those from laboratory combustion due to the dynamics of the gas phase. The need is exemplified for a well-characterized combustion environment for effective use of FT-IR as a diagnostic tool for pilot-scale combustion and for advancing the fundamental understanding of combustion processes.

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