High-frequency vibrational modes at stepped Pt(111) surfaces

Mark Mostoller; Uzi Landman

doi:10.1103/physrevb.20.1755

CHARACTERISTIC VIBRATIONAL MODES OF H2O ADSORBED MOLECULARLY AND DISSOCIATIVELY ON TITANIUM OXIDE CLUSTERS

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633612500861 ◽

2012 ◽

Vol 11 (06) ◽

pp. 1289-1295 ◽

Cited By ~ 1

Author(s):

HONGBO DU ◽

ABIR DE SARKAR ◽

YU JIA ◽

RUI-QIN ZHANG

Keyword(s):

Water Molecule ◽

Raman Spectra ◽

High Frequency ◽

Dissociative Adsorption ◽

Vibrational Modes ◽

High Frequency Range ◽

Frequency Range ◽

Adsorbed State ◽

The One ◽

Ir And Raman

To provide useful information on dissociation of water molecule on ( TiO2 )n clusters for experimental verification, we have calculated the infrared (IR) and Raman spectra of three possible states involved, namely molecularly adsorbed state, metastable state and dissociatively adsorbed state, using density functional theory at the B3LYP/6-311G(d) level. We find that the characteristic bands of H2O molecules below 2000 cm-1 in both IR and Raman spectra vanish upon both molecular and dissociative adsorption of H2O . In the high frequency range of 3600–4200 cm-1, the adsorption caused the single IR peak of water to split into two bands, while the dissociation removed the one at lower frequency and blue shifted slightly the higher frequency band. The two Raman peaks of the water molecule in the same high frequency range were slightly blue shifted upon adsorption but the one at lower frequency was removed upon dissociation, while the one at high frequency blue shifted slightly. The intensities of vibrational modes of water in 3600–4200 cm-1 are generally significantly enhanced upon both molecular and dissociative adsorption. Our results show clearly signatures of dissociation of water molecule into hydroxyl radical at the terminal site.

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High frequency vibrational modes of poly(dA) · poly(dT) and poly(dAT) · poly(dAT)

Journal of Raman Spectroscopy ◽

10.1002/jrs.1250080602 ◽

1979 ◽

Vol 8 (6) ◽

pp. 291-304 ◽

Cited By ~ 8

Author(s):

J. F. Baret ◽

G. P. Carbone ◽

J. Sturm

Keyword(s):

High Frequency ◽

Vibrational Modes

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Coupling of Low- and High-Frequency Vibrational Modes: Broadening in the Infrared Spectrum of F–(H2O)2

The Journal of Physical Chemistry Letters ◽

10.1021/jz4013867 ◽

2013 ◽

Vol 4 (17) ◽

pp. 2964-2969 ◽

Cited By ~ 14

Author(s):

Eugene Kamarchik ◽

Joel M. Bowman

Keyword(s):

Infrared Spectrum ◽

High Frequency ◽

Vibrational Modes

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On the forbidden graphene’s ZO (out-of-plane optic) phononic band-analog vibrational modes in fullerenes

Communications Chemistry ◽

10.1038/s42004-021-00540-z ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Jesús N. Pedroza-Montero ◽

Ignacio L. Garzón ◽

Huziel E. Sauceda

Keyword(s):

High Frequency ◽

Density Functional ◽

Room Temperature ◽

Bulk Material ◽

Characteristic Line ◽

Vibrational Modes ◽

Frequency Range ◽

Functional Theory ◽

Phonon Band ◽

Out Of Plane

AbstractThe study of nanostructures’ vibrational properties is at the core of nanoscience research. They are known to represent a fingerprint of the system as well as to hint the underlying nature of chemical bonds. In this work, we focus on addressing how the vibrational density of states (VDOS) of the carbon fullerene family (Cn: n = 20 → 720 atoms) evolves from the molecular to the bulk material (graphene) behavior using density functional theory. We find that the fullerene’s VDOS smoothly converges to the graphene characteristic line-shape, with the only noticeable discrepancy in the frequency range of the out-of-plane optic (ZO) phonon band. From a comparison of both systems we obtain as main results that: (1) The pentagonal faces in the fullerenes impede the existence of the analog of the high frequency graphene’s ZO phonons, (2) which in the context of phonons could be interpreted as a compression (by 43%) of the ZO phonon band by decreasing its maximum allowed radial-optic vibration frequency. And 3) as a result, the deviation of fullerene’s VDOS relative to graphene may hold important thermodynamical implications, such as larger heat capacities compared to graphene at room-temperature. These results provide insights that can be extrapolated to other nanostructures containing pentagonal rings or pentagonal defects.

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