▎ 摘　　要

Nowadays, first-principles electronic structure calculations can be routinely used to analyze energetics and then to obtain the ground-state structure of a specific material. However, with complicated synthesis routes, nanomaterials are not necessarily always in their thermodynamic ground states. In such situations, computational spectroscopy provides a reliable way for structure characterization. We first briefly introduced the theoretical background of spectrum simulation, focusing on infrared(IR) spectroscopy, Raman spectroscopy, optical absorption,nuclear magnetic resonance (NMR), X-ray photoemission spectroscopy (XPS), and scanning tunneling microscopy/spectroscopy(STM/STS). Then, structure characterization of graphene oxide (GO) was used as an example to demonstrate the power of computational spectroscopy. Comparing experimental spectra with simulated data from different candidate structures, we obtained the information about GO structure. It was unambiguously revealed that experimentally obtained GO samples are in a kinetically constrained metastable state instead of the thermodynamic ground state. Based on computational spectroscopic studies, an updated Lerf model for GO structure was proposed.