Laser-Driven Shock Wave-Induced Triboluminescence of an Organic Crystal:  Toward a Semiquantitative Study

Abstract

A novel technique for studying triboluminescence (TL) of organic crystals is proposed. N-Isopropylcarbazole (NIPCz) crystals were fixed onto a glass plate, whose reverse side was coated with a black pigment that was used as a shock-generating layer. A single fundamental pulse from a Nd 3+ :YAG laser (1064 nm, fwhm ∼ 10 ns) was irradiated onto the shock-generating layer to generate a shock wave, and this resulted in both crystal fracture and TL from the NIPCz crystals. The TL spectrum was almost the same as the fluorescence spectrum of the NIPCz crystals. The dynamic behavior of the crystal fracture and the transient intensity of the TL were shown to be interrelated with each other. The generation of the TL commenced 200 ns after the laser exposure, and this was reproducible irrespective of the NIPCz samples, indicating that the generation and detection timings for TL are controllable with high accuracy by the present technique. In addition, the TL intensity increased with increasing amplitude of the shock wave, as well as the laser fluence. The results presented here demonstrate that the present method provides novel means of investigating TL phenomena semiquantitatively in a noncontact mode.

Experimental and theoretical studies of the decomposition of new imidazole based energetic materials: Model systems

“…Emission can be found from O ±,0 , N ±,0 , N 2 ±,0 , O 2 ±,0 , and C 2 ±,0 , along with that from the molecules comprising the crystals and fragment radicals. The light is called triboluminescence [11][12][13][14][15][16][17][18][19][20] and even laser induced shock waves external to the crystals can generate excited electronic states. 18,[21][22][23][24][25] Note that the ionization energy of N 2 itself is over 15.5 eV and this only generates N 2 + (X)!…”

Radiation of light from powder materials under shock compression

“…The actual volume of adiabatically-compressed gas is probably larger than the shock-compressed liquid volume at the same shock pressure. We adopted this volume to calculate the gas temperature using formula (2). For example, for a shock pressure of 10.0 GPa, the volume of nitrogen gas is calculated to be 0.21 cm 3 /g from formula (1), which is $6 times smaller than the liquid nitrogen density (1.23 cm 3 /g).…”

“…In most cases, such light emission is attributed to thermal radiation because shock compression can easily heat the matter up to thousands of degrees, which gives off intense emission of light over the visible region [1]. In other cases, it is reported that triboluminescence (or mechanoluminescence) has been observed from shock-compressed luminescent materials in laser shock experiments [2,3].…”

Functional Diblock Copolymers for the Integration of Triboluminescent Materials into Polymer Matrices

“…On the other hand, the size also plays an important role in the triboluminescence and the spatial resolution of damage events. [21,22] Crystals achieved by recrystallization from ethanol are needles with lengths around 80 mm [ Figure 5(A)]. They can grow into giant single crystals [500 mm length, Figure 5 Figure 5(D), the triboluminescence of NHEt 3 Eu(dbm) 4 needles, as shown in Figure 5(A), was recorded using a commercially available digital camera.…”