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Structure and vibrations of BenOn (n=3-10) clusters
1Department of Chemistry, Shandong Institute of Light Industry, Shandong, Jinan 250100, PR China. QYH88@EYOU.COM
Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
|September 2, 2006
Summary
Beryllium oxide (Be(n)O(n)) clusters adopt cumulenic ring structures. Their harmonic vibrations show intense infrared-active modes, with frequencies increasing with cluster size.
Area of Science:
- Computational chemistry
- Materials science
- Quantum mechanics
Background:
- Beryllium oxide (Be(n)O(n)) clusters are of interest due to their unique electronic and structural properties.
- Understanding their vibrational characteristics is crucial for predicting their behavior and potential applications.
Purpose of the Study:
- To investigate the structural and harmonic vibrational properties of Be(n)O(n) clusters for n=3-10.
- To characterize the vibrational modes and their intensities.
- To compare the findings with related carbon and boron-nitrogen clusters.
Main Methods:
- Density Functional Theory (DFT) was employed to model the Be(n)O(n) clusters.
- Calculations focused on determining equilibrium geometries and vibrational frequencies.
- Harmonic vibrational analysis was performed to identify characteristic modes.
Main Results:
- All investigated Be(n)O(n) structures adopt cumulenic D(nh) ring configurations with equal bond lengths and alternating bond angles.
- A distinct out-of-plane vibrational mode was identified.
- Three infrared-active degenerate modes were observed, with the highest frequency mode showing extreme intensity and increasing with cluster size, reaching 1597 cm(-1) for n=10.
Conclusions:
- The Be(n)O(n) clusters exhibit stable cumulenic ring structures.
- The vibrational spectra are characterized by intense infrared-active modes, providing a fingerprint for these clusters.
- The structural and bonding characteristics align with those observed in C(2n) and B(n)N(n) clusters, suggesting a common structural motif in these related systems.
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