自成功合成[6,6]碳纳米带(CNB)以来,连续合成了[8,8]CNB和[12,12]CNB。不同尺寸的CNB([2N,2N]CNB;N=2、3、4、5、6、7和8)具有量子尺寸效应,并表现出完全不同的光学性质。在这项工作中,[2N,基于密度泛函理论(DFT)研究2N]CNB。分子体积,孔隙体积,和[2N的稳定性,2N]CNB被调查。[2N,2N]CNB被解释,并给出了吸收峰波长与吸收系数(ε)和尺寸之间的外推公式。[2N,2N]计算CNB,并提供了特征峰的振动模式。最后,[2N,2N]CNB进行了研究,这反映了分子极化的各向异性。[2N的极化率(α)和第二超极化率(γ)的外推公式,2N]给出了不同外部场下的CNB。本文给出的外推公式将有助于预测任意[2N,2N]CNB超出计算能力,为[2N,2N]CNB的理论基础。
Since the successful synthesis of [6,6]carbon nanobelt (CNB), [8,8]CNB and [12,12]CNB have been synthesized successively. CNBs with different sizes ([2N,2N]CNB; N = 2, 3, 4, 5, 6, 7, and 8) have quantum size effects and exhibit completely different optical properties. In this work, the linear and nonlinear optical properties and spectral changes of [2N,2N]CNB are studied based on density functional theory (DFT). The molecular volume, pore volume, and stability of [2N,2N]CNB are investigated. The electron transition mechanism of the one-photon absorption (
OPA) and two-photon absorption (TPA) spectra of [2N,2N]CNB is explained, and the extrapolation formula between the wavelength of the absorption peak and the absorption coefficient (ε) and size is given. The infrared (IR) and Raman spectra of [2N,2N]CNB are calculated, and the vibrational modes of characteristic peaks are provided. Finally, the nonlinear optical properties of [2N,2N]CNB are studied, which reflect the anisotropy of molecular polarization. The extrapolation formulas for the polarizability (α) and second hyperpolarizability (γ) of [2N,2N]CNB under different external fields are given. The extrapolation formulas given in this work will help to predict the linear and nonlinear optical properties of arbitrary [2N,2N]CNB beyond computational power, laying the foundation for the practical application of [2N,2N]CNB\'s theoretical basis.