hydrostatic pressure作用下无取向单壁碳纳米管薄膜的红外光谱研究

hydrostatic pressure作用下单壁碳纳米管束的径向呼吸模式

The radial breathing-like mode of the collapsed Single-walled carbon nanotube bundle under hydrostatic pressure

利用第一性原理计算研究了静水压力下（10，10）单壁碳纳米管束的振动模式和拉曼光谱。详细的分析表明，结构相变（SPT）后，单壁碳纳米管束原有的径向呼吸模式（RBM）消失。在509 cm^{-1}处出现了明显的类RBM模式，可以认为这是SPT发生在单壁碳纳米管束中的一个指纹，并可用于确定SPT后单壁碳纳米管束的微观结构。

内管填充对碳纳米管稳定性的影响：hydrostatic pressure作用下双壁碳纳米管的光谱研究

Stabilization of carbon nanotubes by filling with inner tubes: An optical spectroscopy study on double-walled carbon nanotubes under hydrostatic pressure

利用光学光谱技术研究了双壁碳纳米管束在静水压力下的光学跃迁，证明了内管填充对碳纳米管的稳定作用。以富勒烯豆荚为原料制备了双壁碳纳米管薄膜，并用高分辨透射电镜和光学光谱对其进行了表征。与单壁碳纳米管相比，外管中的光学跃迁的压力诱导红移在低于$\sim$ 10 GPa时显著更小，这表明由于内管已经处于低压下而增强的机械稳定性。在临界压力P $_d$ $\approx$ 12 GPa处的异常信号表示管横截面的压力诱导变形的开始。P $_d$的值与理论预测的具有相似平均直径的双壁碳纳米管束中的压力诱导结构转变非常一致。

Behavior of the van der Waals force between a plate and a single-walled carbon nanotube under uniform hydrostatic pressure: a theoretical study

We study the behaviour of the non-retarded van der Waals force between a planar substrate and a single-walled carbon nanotube, assuming that the system is immersed in a liquid medium which exerts hydrostatic pressure on the tube's surface, thereby altering its cross-section profile. The shape of the latter is described as a continual structure characterized by its symmetry index $n$. Two principle mutual positions of the tube with respect to the substrate are studied: when one keeps constant the minimal separation between the surfaces of the interacting objects; when the distance from the tube…

无应变最平坦单壁碳纳米管在压力作用下的形状转变

Shape transition of unstrained flattest single-walled carbon nanotubes under pressure

单壁碳纳米管的截面在静水压力作用下可以被压扁。一个例子是单壁碳纳米管的截面从原始的圆形形状连续变形为椭圆形形状，然后变形为花生状形状。在凸形和凹形之间的可逆变形过渡点处，纳米管的侧壁最平坦。这种最扁平的管子有许多吸引人的特性。本文提出了一种近似方法来确定这种无应变扁管的平衡形状和曲率分布。我们的结果与最近的数值计算结果符合得很好，可以应用于单壁碳纳米管压控电性能的研究。本方法也可用于研究其他无机和有机变形管状结构。

多壁碳纳米管的压力诱导结构转变

Pressure-induced structural transitions in multi-walled carbon nanotubes

我们展示了一种新的横截面变形，称为径向弯曲，多壁碳纳米管（MWNTs）在静水压力下。基于连续弹性近似的理论分析表明，由十个以上的同心壁组成的多壁碳纳米管在临界压力$p_c \simeq 1$ GPa下发生弹性形变，在该压力以上，截面的圆形形状变成径向波纹状。通过调节最内层管的直径和组成壁的数量，已经观察到了各种不同的微扰模式，这是多壁碳纳米管的核壳结构的直接结果。

On the atomistic energetics of carbon nanotube collapse from AIREBO potential

Molecular dynamics simulations based on the adaptive intermolecular reactive empirical bond order (AIREBO) were performed to probe hydrostatic pressure induced collapse of single-walled and double-walled carbon nanotubes. It was unveiled that the torsion term, which is a specific potential component involved in the AIREBO scheme, plays a vital role in stabilizing fully collapsed cross-sections of the carbon nanotubes. Evolution of the cross-sectional deformation along the loading-unloading curve was also elucidated, showing strong dependence on the presence of a structural defect on the outer …