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Low-energy electron interactions with tungsten hexacarbonyl--W(CO)6
K Wnorowski1, M Stano, C Matias
1Department of Chemistry, Siedlce University, 3 Maja 54, 08-110 Siedlce, Poland.
Rapid Communications in Mass Spectrometry : RCM
|August 1, 2012
Summary
Low-energy electrons cause tungsten hexacarbonyl (W(CO)(6)) to decompose, forming fragment anions rather than a stable molecule. This dissociative electron attachment (DEA) process explains contamination in surface modification techniques.
Area of Science:
- Physical Chemistry
- Surface Science
- Materials Science
Background:
- Low-energy secondary electrons are crucial for material modification.
- Organometallic molecules like W(CO)(6) are used in electron-based metallic structure formation.
- Understanding electron-molecule interactions is key to controlling surface modification processes.
Purpose of the Study:
- Investigate low-energy electron attachment to W(CO)(6) in the gas phase.
- Elucidate reaction mechanisms relevant to surface modification.
- Determine the fate of W(CO)(6) upon electron impact.
Main Methods:
- Utilized crossed electron/molecular beam setups.
- Employed a high-resolution electron monochromator and quadrupole mass spectrometer for cross-section measurements.
- Used a double focusing mass spectrometer to study metastable anion decays.
Main Results:
- W(CO)(6) efficiently decomposed upon low-energy electron attachment (0-14 eV).
- No stable W(CO)(6)(-) anion was observed; sequential loss of CO ligands occurred.
- Fragment anions W(CO)(5)(-), W(CO)(4)(-), W(CO)(3)(-), and W(CO)(2)(-) were detected, but not W(-).
Conclusions:
- Dissociative electron attachment (DEA) to W(CO)(6) results in significant dissociation.
- Complete loss of all CO ligands was not observed via DEA.
- DEA reactions near the irradiation spot may contribute to deposit contamination in beam deposition.
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