Systematic study of hadronic excitation energy using the Schottky anomaly

This paper aims to study the nonlinear absorption characteristics of palladium nanoparticles (PdNPs) at off-resonant wavelengths. For this purpose, multi-wavelength (500–650 nm) nanosecond Z-scan technique was used. The experimental results indicate that saturated absorption (SA) and the transition from SA to reverse saturated absorption (RSA) can occur, and depends on the excitation wavelength and energy. When the excitation wavelength is constant, with the increase of excitation energy, PdNPs change from SA to RSA. When the excitation energy is constant, with the excitation wavelength approaching surface plasmon resonance (SPR), PdNPs change from SA to RSA. This phenomenon of SA and RSA under multi-wavelength excitation in the off-resonant region provides a supplement for the systematic study of the nonlinear absorption of PdNPs.

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Structure-Photochemical Function Relationships in Nitrogen-Containing Heterocyclic Aromatic Photobases Derived from Quinoline

10.26434/chemrxiv.11312642.v1 ◽

2019 ◽

Author(s):

Sophya Alamudun ◽

Kyle Tanovitz ◽

April Fajardo ◽

Kaitlind Johnson ◽

Andy Pham ◽

...

Keyword(s):

Excited State ◽

Charge Transfer ◽

Excitation Energy ◽

Systematic Study ◽

Experimental Studies ◽

Substituent Effects ◽

Vertical Excitation ◽

Vertical Excitation Energy ◽

Heterocyclic Aromatics ◽

A Charge

Photobases are compounds which become strong bases after electronic excitaton into a charge-transfer excited state. Recent experimental studies have highlighted the photobasicity of the 5-R quinoline compounds, demonstrating a strong substituent dependence to the pKa*. Here we describe our systematic study of how the photobasicity of four families of nitrogen-containing heterocyclic aromatics are tuned through substituents. We show that substituent position and identity both significantly impact the pKa*. We demonstrate that the substituent effects are additive and identify many disubstituted compounds with substantially greater photobasicity than the most photobasic 5-R quinoline compound identified previously. We show that the addition of a second fused benzene ring to quinoline, along with two electron-donating substituents, lowers the vertical excitation energy into the visible while still maintaining a pKa* > 14. Overall, the structure-function relationships developed in this study provide new insights to guide the development of new photocatalysts that employ photobasicity.

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Structure-Photochemical Function Relationships in Nitrogen-Containing Heterocyclic Aromatic Photobases Derived from Quinoline

10.26434/chemrxiv.11312642 ◽

2020 ◽

Author(s):

Sophya Alamudun ◽

Kyle Tanovitz ◽

April Fajardo ◽

Kaitlind Johnson ◽

Andy Pham ◽

...

Keyword(s):

Excited State ◽

Charge Transfer ◽

Excitation Energy ◽

Systematic Study ◽

Experimental Studies ◽

Substituent Effects ◽

Vertical Excitation ◽

Vertical Excitation Energy ◽

Heterocyclic Aromatics ◽

A Charge

Photobases are compounds which become strong bases after electronic excitaton into a charge-transfer excited state. Recent experimental studies have highlighted the photobasicity of the 5-R quinoline compounds, demonstrating a strong substituent dependence to the pKa*. Here we describe our systematic study of how the photobasicity of four families of nitrogen-containing heterocyclic aromatics are tuned through substituents. We show that substituent position and identity both significantly impact the pKa*. We demonstrate that the substituent effects are additive and identify many disubstituted compounds with substantially greater photobasicity than the most photobasic 5-R quinoline compound identified previously. We show that the addition of a second fused benzene ring to quinoline, along with two electron-donating substituents, lowers the vertical excitation energy into the visible while still maintaining a pKa* > 14. Overall, the structure-function relationships developed in this study provide new insights to guide the development of new photocatalysts that employ photobasicity.

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SYSTEMATIC STUDY OF THE MANY-PARTICLE AND MANY-HOLE STATES IN AND AROUND THE ISLAND OF INVERSION

International Journal of Modern Physics E ◽

10.1142/s0218301311018915 ◽

2011 ◽

Vol 20 (04) ◽

pp. 893-896 ◽

Cited By ~ 5

Author(s):

MASAAKI KIMURA

Keyword(s):

Molecular Dynamics ◽

Excitation Energy ◽

Excited States ◽

Systematic Study ◽

Ground State ◽

Negative Parity ◽

Parity Assignment ◽

Island Of Inversion ◽

The Many

Deformation and many particle and many hole configurations in the island of inversion are investigated with Antisymmetrized Molecular Dynamics (AMD). The result suggests the coexistence of many particle and many hole configurations with different deformation at small excitation energy. In the case of 33 Mg , we suggest the negative-parity assignment for the ground state. Other particle hole configurations are predicted as the excited states.

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Structure-Photochemical Function Relationships in Nitrogen-Containing Heterocyclic Aromatic Photobases Derived from Quinoline

10.26434/chemrxiv.11312642.v2 ◽

2020 ◽

Author(s):

Sophya Alamudun ◽

Kyle Tanovitz ◽

April Fajardo ◽

Kaitlind Johnson ◽

Andy Pham ◽

...

Keyword(s):

Excited State ◽

Charge Transfer ◽

Excitation Energy ◽

Systematic Study ◽

Experimental Studies ◽

Substituent Effects ◽

Vertical Excitation ◽

Vertical Excitation Energy ◽

Heterocyclic Aromatics ◽

A Charge

Photobases are compounds which become strong bases after electronic excitaton into a charge-transfer excited state. Recent experimental studies have highlighted the photobasicity of the 5-R quinoline compounds, demonstrating a strong substituent dependence to the pKa*. Here we describe our systematic study of how the photobasicity of four families of nitrogen-containing heterocyclic aromatics are tuned through substituents. We show that substituent position and identity both significantly impact the pKa*. We demonstrate that the substituent effects are additive and identify many disubstituted compounds with substantially greater photobasicity than the most photobasic 5-R quinoline compound identified previously. We show that the addition of a second fused benzene ring to quinoline, along with two electron-donating substituents, lowers the vertical excitation energy into the visible while still maintaining a pKa* > 14. Overall, the structure-function relationships developed in this study provide new insights to guide the development of new photocatalysts that employ photobasicity.

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Quantitative parallel EELS spectrum imaging developed as a new tool in AEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013064x ◽

1992 ◽

Vol 50 (2) ◽

pp. 1202-1203

Author(s):

Gianluigi Botton ◽

Gilles L'espérance

Keyword(s):

Statistical Analysis ◽

Spatial Resolution ◽

Personal Computer ◽

Systematic Study ◽

Present Author ◽

Chemical Elements ◽

Detection Limits ◽

Research Groups ◽

Quantitative Performance ◽

Spectrum Imaging

As interest for parallel EELS spectrum imaging grows in laboratories equipped with commercial spectrometers, different approaches were used in recent years by a few research groups in the development of the technique of spectrum imaging as reported in the literature. Either by controlling, with a personal computer both the microsope and the spectrometer or using more powerful workstations interfaced to conventional multichannel analysers with commercially available programs to control the microscope and the spectrometer, spectrum images can now be obtained. Work on the limits of the technique, in terms of the quantitative performance was reported, however, by the present author where a systematic study of artifacts detection limits, statistical errors as a function of desired spatial resolution and range of chemical elements to be studied in a map was carried out The aim of the present paper is to show an application of quantitative parallel EELS spectrum imaging where statistical analysis is performed at each pixel and interpretation is carried out using criteria established from the statistical analysis and variations in composition are analyzed with the help of information retreived from t/γ maps so that artifacts are avoided.

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