On the Electronic Structure of Cu Chlorophyllin and Its Breakdown Products: A Carbon K-Edge X-ray Absorption Spectroscopy Study

Abstract

Using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, the carbon backbone of sodium copper chlorophyllin (SCC), a widely used chlorophyll derivative, and its breakdown products are analyzed to elucidate their electronic structure and physicochemical properties. Using various sample preparation methods and complementary spectroscopic methods (including UV/Vis, X-ray photoelectron spectroscopy), a comprehensive insight into the SCC breakdown process is presented. The experimental results are supported by density functional theory calculations, allowing a detailed assignment of characteristic NEXAFS features to specific C bonds. SCC can be seen as a model system for the large group of porphyrins; thus, this work provides a novel and detailed description of the electronic structure of the carbon backbone of those molecules and their breakdown products. The achieved results also promise prospective optical pump/X-ray probe investigations of dynamic processes in chlorophyll-containing photosynthetic complexes to be analyzed more precisely.

Unravelling the effect of fluorinated ligands in hybrid EUV photoresists by X-ray spectroscopy

“…In particular, NEXAFS spectroscopy was performed using scanning transmission soft X-ray microscopy (STXM). 44,45 This technique enables recording X-ray absorption in the soft X-ray regime with a spatial resolution of down to 20 nm. The combination of EUV exposure and ex situ STXM analysis is thus a powerful way to investigate the chemical changes undergone by the resists upon EUV exposure.…”

Sodium Copper Chlorophyllin Catalyzed Chemoselective Oxidation of Benzylic Alcohols and Diarylmethanes in Water

“…Sodium copper chlorophyllin (C 34 H 31 CuN 4 Na 3 O 6 , SCC; Figure 1 ) is a semi-synthetic, water-soluble derivative of chlorophyll and is widely used in the food and medicine industries [ 18 , 19 , 20 ]. Due to its characteristic tetrapyrrole structure, the photochemical properties of SCC have been well studied by organic photovoltaics and optical spectroscopy [ 21 , 22 , 23 , 24 , 25 ]. However, the effectiveness of SCC as a catalyst in organic reactions has yet to be explored in-depth [ 26 ].…”

Photosensitizer Using Visible Light

“…[15][16][17] Moreover, the photochemical behaviour of chlorophyllin sodium copper salt have been studied using organic photovoltaics and optical spectroscopy. [18][19][20][21][22] Nonetheless, the utilization of SCC as a photosensitizer in organic reactions has yet to be investigated thoroughly. 23,24 A drawback of using chlorophyll as photosensitizer is its instability under thermally or photochemically conditions.…”