Direct observation of photoinduced bent nitrosyl excited-state complexes
Abstract
Ground state structures with side-on nitrosyl ({eta}{sup 2}-NO) and isonitrosyl (ON) ligands have been observed in a variety of transition-metal complexes. In contrast, excited state structures with bent-NO ligands have been proposed for years but never directly observed. Here we use picosecond time-resolved infrared spectroscopy and density functional theory (DFT) modeling to study the photochemistry of Co(CO){sub 3}(NO), a model transition-metal-NO compound. Surprisingly, we have observed no evidence for ON and {eta}{sup 2}-NO structural isomers, but have observed two bent-NO complexes. DFT modeling of the ground and excited state potentials indicates that the bent-NO complexes correspond to triplet excited states. Photolysis of Co(CO){sub 3}(NO) with a 400-nm pump pulse leads to population of a manifold of excited states which decay to form an excited state triplet bent-NO complex within 1 ps. This structure relaxes to the ground triplet state in ca. 350 ps to form a second bent-NO structure.
- Authors:
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- Chemical Sciences Division
- OSTI Identifier:
- 944986
- Report Number(s):
- LBNL-1346E
Journal ID: 1089-5639; TRN: US200902%%1170
- DOE Contract Number:
- DE-AC02-05CH11231
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory
- Additional Journal Information:
- Journal Volume: 112; Journal Issue: 37
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; DECAY; EXCITED STATES; FUNCTIONALS; GROUND STATES; ISOMERS; PHOTOCHEMISTRY; PHOTOLYSIS; SIMULATION; SPECTROSCOPY; TRIPLETS
Citation Formats
Sawyer, Karma R, Steele, Ryan P, Glascoe, Elizabeth A, Cahoon, James F, Schlegel, Jacob P, Head-Gordon, Martin, and Harris, Charles B. Direct observation of photoinduced bent nitrosyl excited-state complexes. United States: N. p., 2008.
Web. doi:10.1021/jp802705w.
Sawyer, Karma R, Steele, Ryan P, Glascoe, Elizabeth A, Cahoon, James F, Schlegel, Jacob P, Head-Gordon, Martin, & Harris, Charles B. Direct observation of photoinduced bent nitrosyl excited-state complexes. United States. https://doi.org/10.1021/jp802705w
Sawyer, Karma R, Steele, Ryan P, Glascoe, Elizabeth A, Cahoon, James F, Schlegel, Jacob P, Head-Gordon, Martin, and Harris, Charles B. 2008.
"Direct observation of photoinduced bent nitrosyl excited-state complexes". United States. https://doi.org/10.1021/jp802705w. https://www.osti.gov/servlets/purl/944986.
@article{osti_944986,
title = {Direct observation of photoinduced bent nitrosyl excited-state complexes},
author = {Sawyer, Karma R and Steele, Ryan P and Glascoe, Elizabeth A and Cahoon, James F and Schlegel, Jacob P and Head-Gordon, Martin and Harris, Charles B},
abstractNote = {Ground state structures with side-on nitrosyl ({eta}{sup 2}-NO) and isonitrosyl (ON) ligands have been observed in a variety of transition-metal complexes. In contrast, excited state structures with bent-NO ligands have been proposed for years but never directly observed. Here we use picosecond time-resolved infrared spectroscopy and density functional theory (DFT) modeling to study the photochemistry of Co(CO){sub 3}(NO), a model transition-metal-NO compound. Surprisingly, we have observed no evidence for ON and {eta}{sup 2}-NO structural isomers, but have observed two bent-NO complexes. DFT modeling of the ground and excited state potentials indicates that the bent-NO complexes correspond to triplet excited states. Photolysis of Co(CO){sub 3}(NO) with a 400-nm pump pulse leads to population of a manifold of excited states which decay to form an excited state triplet bent-NO complex within 1 ps. This structure relaxes to the ground triplet state in ca. 350 ps to form a second bent-NO structure.},
doi = {10.1021/jp802705w},
url = {https://www.osti.gov/biblio/944986},
journal = {Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory},
number = 37,
volume = 112,
place = {United States},
year = {Sat Jun 28 00:00:00 EDT 2008},
month = {Sat Jun 28 00:00:00 EDT 2008}
}