Nawagamuwage Sithara U, Williams Elliot S, Islam Md Muhaiminul, Parshin Igor V, Burin Alexander L, Busschaert Nathalie, Rubtsov Igor V
Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States.
J Phys Chem B. 2024 Sep 12;128(36):8788-8796. doi: 10.1021/acs.jpcb.4c03386. Epub 2024 Sep 1.
In an effort to increase the speed and efficiency of ballistic energy transport via oligomeric chains, we performed measurements of the transport in compounds featuring long alkyl chains of up to 37 methylene units. Compounds of the N-(CH)-COOMe type (denoted as azME) were synthesized with = 5, 10, 15, 19, 28, 37 and studied using relaxation-assisted two-dimensional infrared spectroscopy. The speed of the ballistic transport, initiated by the N tag excitation, increased ca. 3-fold for the longer chains ( = 19-37) compared to the shorter chains, from 14.7 to 48 Å/ps, in line with an earlier prediction (Nawagamuwage et al. 2021, , , 7546). Modeling, based on solving numerically the Liouville equation, was capable of reproducing the experimental data only if three wavepackets are included, involving CH twisting (Tw), wagging (W), and rocking (Ro) chain bands. The approaches for designing molecular systems featuring a higher speed and efficiency of energy transport are discussed.
为了提高通过低聚链进行弹道能量传输的速度和效率，我们对具有长达37个亚甲基单元的长烷基链的化合物中的传输进行了测量。合成了N-(CH)-COOMe类型的化合物（表示为azME），其中n = 5、10、15、19、28、37，并使用弛豫辅助二维红外光谱进行了研究。由N标签激发引发的弹道传输速度，与较短链相比，较长链（n = 19 - 37）提高了约3倍，从14.7 Å/ps提高到48 Å/ps，这与早期预测一致（纳瓦加穆瓦格等人，2021年，……，7546）。基于对刘维尔方程进行数值求解的建模，只有在包含三个波包时才能重现实验数据，这三个波包涉及CH扭曲（Tw）、摆动（W）和摇摆（Ro）链带。讨论了设计具有更高能量传输速度和效率的分子系统的方法。
