Ultrahigh time-resolution vibrational spectroscopy of shocked molecular solids

Hambir, Selezion A.; Franken, Jens; Hare, David E.; Chronister, Eric L.; Baer, Bruce J.; Dlott, Dana D.

doi:10.1063/1.364269

Cited by 70 publications

(127 citation statements)

References 29 publications

Supporting

Mentioning

127

Contrasting

Order By: Relevance

“…The pressure is the main factor responsible for the Raman peak shift, the influences of temperature and other factors are secondary, [14] so the magnitude of Raman peak shift ν (cm −1 ) could be seen as a gauge of pressure P (GPa). The relationship between the two quantities is linear when the pressure is not too high:…”

Section: Raman Peak-shift Simulationmentioning

confidence: 99%

The characteristics of laser‐driven shock wave investigated by time‐resolved Raman spectroscopy

Song

Zheng

et al. 2011

J Raman Spectroscopy

View full text Add to dashboard Cite

An accurate and simple method, Raman peak-shift simulation, is proposed to determine the characteristics of a laser-driven shock wave. Using the principle of the Raman peaks shifting at high pressure and the pressure distribution in the gauge layer, the profile of the Raman peak can be numerically simulated. Combined with time-resolved Raman spectroscopy, some main characteristics of the shock wave were determined. In the experiment, polycrystalline anthracene was used as the pressure gauge. The pump-probe technique was used to obtain the time-resolved Raman spectra of anthracene under shock loading. The velocity of the shock wave, the peak pressure and the rise time of the shock front were determined by simulating the experimental spectra numerically. The result shows that the method of Raman peak-shift simulation is effective in obtaining the characteristics of a laser-driven shock wave.

show abstract

Section: Raman Peak-shift Simulationmentioning

confidence: 99%

The characteristics of laser‐driven shock wave investigated by time‐resolved Raman spectroscopy

Song

Zheng

et al. 2011

J Raman Spectroscopy

View full text Add to dashboard Cite

show abstract

“…In the past, vibrational spectroscopy has been applied successfully to study various materials subjected to shock wave compression. [13][14][15][16][17][18][19][20][21] There have also been attempts to obtain vibrational spectra of PETN under shock wave and static high-pressure loading. 22, 23 However, these attempts were hampered by experimental difficulties and by the lack of understanding of the complex structure of the PETN vibrational spectrum.…”

Section: Introductionmentioning

confidence: 99%

Vibrational Properties and Structure of Pentaerythritol Tetranitrate

Gruzdkov

Gupta

2001

J. Phys. Chem. A

View full text Add to dashboard Cite

Geometry optimizations and normal-mode analyses of the pentaerythritol tetranitrate (PETN) conformer belonging to the S 4 molecular point group and comprising the crystalline solid were performed using density functional theory methods (B3LYP and B3PW91). The basis sets used in this study were 6-31G(d) and 6-311+G(d,p). The structural results are in good agreement with experimental X-ray diffraction data. The predicted bond lengths and bond angles are accurate to within ∼2.5% and ∼1.2%, respectively. Raman and infrared spectra of crystalline PETN were measured and compared with the calculated spectra. The calculated and measured spectra agree very well in the spectral region below 1100 cm -1 ; the agreement is satisfactory for frequencies higher than 1100 cm -1 . On the basis of the calculations and analyses, normal mode assignments were made and mode symmetries determined.

show abstract

“…It is noted here that, in general, Raman peaks become broader and shift towards red with temperature, and hence the increase of Raman frequency under shock compression is smaller than that under static isothermal compression because the temperature is significantly increased owing to the adiabatic nature of shock compression. 17 Raman frequency shifts of iodobenzene and nitrobenzene under shock compression have not been known so far. Most notable is the very small peak shifts of the NO 2 symmetric stretching mode.…”

mentioning

confidence: 99%

In situRaman spectroscopy of shock-compressed benzene and its derivatives

Kobayashi

Sekine

2000

Phys. Rev. B

View full text Add to dashboard Cite

Real-time Raman spectra of shock compressed benzene and its monosubstitutes, iodobenzene, and nitrobenzene, have been measured in the pressure range up to 7.5 GPa. Spectral peaks show almost linear blueshifts against shock pressure. However, nitrobenzene, compared to the other two compounds, shows smaller shifts. Especially the increase in Raman frequency of the NO 2 stretching mode ͑1346 cm Ϫ1 ͒ is extremely small. An intermolecular interaction between nitrobenzene molecules seems responsible for this behavior.In order to understand shock-induced phenomena, it is essential to obtain real-time information of materials under shock compression. The dynamic nature of shock compression, i.e., fast rise, short duration, and fast release of shock loading, often generates nonequilibrium states or unstable intermediates in the process of shock compression and usually they are not quenchable. In situ laser spectroscopy is a good tool to investigate those transient states or species. It can provide real-time information on shock-induced structural and chemical changes. Some sophisticated applications of laser spectroscopy to in situ observation of shock-induced phenomena have been reported over the last couple of decades. 1-6 In this paper we report shock-induced changes in vibrational spectra of benzene, iodobenzene, and nitrobenzene measured by a single-pulse laser Raman spectrometer in conjunction with a plate impact technique. It was found that shock-induced changes in Raman spectra of nitrobenzene are quite different from those of benzene and iodobenzene. Spectral peak shifts ͑blue shifts͒ against shock pressure were found smaller for nitrobenzene compared to those of benzene and iodobenze, especially the NO 2 stretching mode of nitrobenzene showed very small shifts. The relatively strong intermolecular interaction existing between nitrobenzene molecules seems to play an essential role. In this study we determined Raman frequency changes against shock pressures for three very common organic solvents. This kind of data can also be used as pressure calibration standards for certain shock experiments. For example, unlike shock experiments by plate impact, in some laser shock experiments pressure determination is difficult and may involve large uncertainties. In such cases, shock pressures can be easily determined by measuring the spectral shift for a standard sample whose spectral peak shift vs shock pressure data are available.In general vibrational frequencies of stretching modes increase with pressure because bond lengths are reduced 7 under pressure and effective force constants at the new equilibrium positions are usually larger than those at the original equilibrium position. This simplified description is qualitatively valid at relatively low pressures where the compression energy is small compared to the electronic energies. 8

show abstract

Ultrahigh time-resolution vibrational spectroscopy of shocked molecular solids

Cited by 70 publications

References 29 publications

The characteristics of laser‐driven shock wave investigated by time‐resolved Raman spectroscopy

The characteristics of laser‐driven shock wave investigated by time‐resolved Raman spectroscopy

Vibrational Properties and Structure of Pentaerythritol Tetranitrate

In situRaman spectroscopy of shock-compressed benzene and its derivatives

Contact Info

Product

Resources

About