Theoretical Insights into the Geometrical Evolution, Photoelectron Spectra, and Vibrational Properties of YGe_n^– (n = 6–20) Anions: From Y-Linked to Y-Encapsulated Structures

Abstract

The structural evolution behavior of germanium anionic clusters doped with the rare-earth metal yttrium, YGe n − (n = 6−20), has been investigated using a mPW2PLYP density functional scheme and an ABCluster structure searching technique. The results reveal that with increasing cluster size n, the structure evolution pattern is from the Y-linked framework (n = 10−14), where Y serves as a linker (the Y atom bridges two germanium subclusters), to the Y-encapsulated framework (n = 15−20), where the Y atom is located in the center of the Ge cage. The simulated PES spectra show satisfying agreement with the experimental PES spectra for n = 12−20, which reveals that the global minimum structures reported here are reliable. In particular, the anionic YGe 16 − nanocluster is found to be the most stable structure in the size range of n = 6−20 through analyzes of the relative stability, highest occupied molecular orbital (HOMO)−lowest unoccupied molecular orbital (LUMO) gap, spherical jellium model, and isochemical shielding surface. Moreover, spectral properties such as infrared and Raman spectra were reported. In addition, the UV−vis spectra of the YGe 16− nanocluster are in good agreement with solar energy distribution, showing that such substances serve as multifunctional building blocks to be potentially used in optoelectronic devices or solar energy converters.

Structural evolution and electronic properties of cerium doped germanium anionic nanocluster CeGen− (n = 5–17): Theoretical investigation

“…Additionally, Zhang, with others, employed the DFT method to investigate the geometry growth of LuGe n q (n = 2-14, q = 0, À1) based on the pentagonal bipyramid shapes, thereby establishing a growth pattern [31]. Besides, our research also focuses on the theoretical study of the RE-based germanium cluster, that is, Sc, Y, Lu, and Gd doped germanium clusters [32][33][34][35]. The consequence of such TM or RE-doped germanium nanocluster exhibits a variety of prominent properties that can be potentially applied in magnetic, luminescent, electronic, and energy-conversion devices.…”