Infrared absorption of GeNNO isolated in solid Ar

Area of Science:

• Inorganic Chemistry
• Spectroscopy
• Computational Chemistry

Background:

• The study investigates the reaction products of germanium vapor and nitrous oxide (N2O) under cryogenic conditions.
• Understanding the formation and properties of novel germanium-nitrogen-oxygen compounds is crucial for materials science and chemical synthesis.

Purpose of the Study:

• To synthesize and characterize new germanium-nitrogen-oxygen (GeNNO) species.
• To elucidate the structural and vibrational properties of these newly formed molecules.
• To investigate the photochemical reactivity of the synthesized GeNNO species.

Main Methods:

• Codeposition of atomic germanium vapor and nitrous oxide (N2O) onto a substrate at 11 K.
• Infrared (IR) absorption spectroscopy to detect and analyze molecular vibrations.
• Quantum-chemical calculations using density-functional theory (DFT) with B3LYP /aug-cc-pVTZ functional.

Main Results:

• Identification of infrared absorption lines attributed to singlet GeNNO, characterized by prominent peaks at 1443.7, 1102.4, and 784.0 cm(-1).
• Observation of additional spectral features assigned to vibrational overtones and combinations of GeNNO, as well as tentative assignments for triplet GeONN and singlet cyc-Ge-eta(2)[NN(O)].
• DFT calculations predicted stable structures including GeNNO (singlet/triplet), cyc-Ge-eta(2)[NN(O)] (singlet/triplet), GeONN (singlet/triplet), and GeNON (singlet), consistent with experimental isotopic data.

Conclusions:

• The study successfully synthesized and characterized novel germanium-nitrogen-oxygen molecules, primarily singlet GeNNO, using cryogenic codeposition and spectroscopic analysis.
• Photochemical experiments demonstrated that singlet GeNNO decomposes into germanium monoxide (GeO) upon irradiation with UV or visible light.
• Computational modeling provided theoretical support for the experimental findings, validating the proposed structures and vibrational modes of the observed species.