Construction of high-throughput magnetic circular dichroism measurement system and its application to research on magnetic and optical properties of phthalocyanine complexes

Magnetic circular dichroism (MCD) spectroscopy is a powerful method for evaluating the electronic structure and magnetic and optical properties of molecules. In particular, MCD measurements have been performed on phthalocyanines and porphyrins with various central metal ions, axial ligands, and substituents to elucidate their properties. It is essential to develop a robust high-throughput technique to perform these measurements comprehensively and efficiently. However, MCD spectroscopy requires very high optical quality for each component of the instrument, and even slight cell distortions can impair the baseline flatness. Consequently, when versatility and data quality are important, an optical system designed for a microplate reader is not suitable for the MCD spectrometer. Therefore, in this study, we develop a new magnetic flow-through cell and combine it with an existing CD spectrometer and autosampler to construct a high-throughput system. The effectiveness and performance of this new system are then evaluated. In addition, based on the MCD and absorption spectra of various phthalocyanine complexes, the effects of substituents and solvents on their magnetic and optical properties and the causes of these effects are discussed. The results demonstrate that this system is effective for the evaluation of the physicochemical properties of various phthalocyanine complexes.

Attenuated Total Reflection Infrared and Far-Infrared, and Raman Spectroscopy Studies of Minerals, Rocks, and Biogenic Minerals

Attenuated total reflection infrared (ATR-IR, 4000-400 cm-1), ATR-far-IR (ATR-FIR, 400-50 cm-1), and Raman spectra (4000-10 cm-1) were measured for calcium carbonate, three kinds of minerals (calcite, aragonite, and quartz), two kinds of rocks (obsidian and pumice), and four kinds of biogenic minerals, i.e., coral (aragonite), Ruditapes philippinarum (aragonite), Meretrix lusoria (aragonite), and Corbicula japonica (aragonite), to investigate the polymorphism of minerals and biogenic minerals, differences in the crystal structure among aragonite and aragonite biogenic minerals, water in the minerals and biogenic minerals, Boson peaks of obsidian and pumice, very small amounts of carotenoids in the three kinds of shells, and so on. In this study, we put some emphasis on the low-frequency region of IR (FIR) and Raman spectra. ATR-FIR spectra were measured down to 50 cm-1 and Raman spectra were obtained down to 10 cm-1. Second derivative spectra were calculated for the FIR spectra. It has been found from the present study that the FIR spectra are the most powerful for exploring polymorphism and differences in the crystal structure among aragonite and aragonite biogenic minerals. A Boson peak, which is a characteristic low-frequency Raman band for amorphous materials, was observed at around 40 cm-1 in the Raman spectra of obsidian and pumice. The Boson peak of pumice is located at a lower frequency by 12 cm-1 than that of obsidian, indicating that the mean atomic volume of pumice is larger than that of obsidian. The present study has revealed that IR spectra are useful to investigate the amounts and structure of fluid and bound water. Moreover, it has also been found that Raman spectra can detect a very tiny amount of carotenoids in the shells due to the resonance Raman effect.

Electronic structure analysis of phthalocyanine complexes using magnetic circular dichroism and magnetic circularly polarized luminescence spectroscopy

In the study of phthalocyanine complexes using magnetic circular dichroism (MCD) spectroscopy, the electronic structure of excited states is generally discussed based on the rigid-shift approximation, in which the band profiles for left-handed circularly polarized (lcp) and right-handed circularly polarized (rcp) light are assumed to be the same. This assumption may not necessarily be valid for cases where there are multiple initial states having different geometries. Magnetic circularly polarized luminescence (MCPL) from phthalocyanine complexes can be regarded as an example of such cases, since the two degenerate emission states are split in a magnetic field and can undergo a structural deformation. Here, we investigated an alternative approach, where the lcp and rcp components are independently determined. This method, which we refer to as the direct-separation approach, allows direct determination of the distribution of the two emission states as well as the orbital angular momentumL z $$ \left|{L}_z\right| $$ . Using this approach,L z $$ \left|{L}_z\right| $$ and the distribution were determined from MCD and MCPL spectra of a series of phthalocyanine complexes. Comparison of the two methods shows that the rigid-shift and the direct-separation approaches give practically equivalent results for the systems under study, but the latter is advantageous for systems where the former is not applicable.

Assessing the effect of dialogue on altruism toward future generations: A preliminary study

Introduction

Despite the abundance of evidence on climate change and its consequences on future generations, people, in general, are still reluctant to change their actions and behaviors toward the environment that would particularly benefit posterity. In this study, we took a preliminary step in a new research direction to explore humans' altruistic behavior toward future generations of people and whether it can be affected by dialogue.

Methods

We used an android robot called Telenoid as a representative of future generations by explaining that the robot is controlled by an Artificial Intelligence (AI) living in a simulation of our world in the future. To measure people's altruistic behavior toward it, we asked the participants to play a round of the Dictator Game with the Telenoid before having an interactive conversation with the Telenoid and then playing another round.

Results

On average, participants gave more money to the Telenoid in the second round (after having an interactive conversation). The average amount of money increased from 20% in the first to about 30% in the second round.

Discussion

The results indicate that the conversation with the robot might have been responsible for the change in altruistic behavior toward the Telenoid. Contrary to our expectations, the personality of the participants did not appear to have an influence on their change of behavior, but other factors might have contributed. We finally discuss the influence of other possible factors such as empathy and the appearance of the robot. However, the preliminary nature of this study should deter us from making any definitive conclusions, but the results are promising for establishing the ground for future experiments.