Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Toughness and Hardness of Aggregate

Toughness and Hardness of Aggregate

Toughness and hardness are critical properties of aggregate materials used in concrete, particularly on pavement surfaces and industrial flooring subjected to heavy loads. Toughness is defined as the aggregate's resistance to failure by impact and is measured by the aggregate impact value (AIV). For this, the aggregate impact value test is performed, wherein the impact is delivered by a standard hammer, which falls freely under its own weight onto the aggregates. The aggregates fragment in...

Multiple Comparison Tests

Multiple Comparison Tests

Multiple comparison test, abbreviated as MCT, is a post hoc analysis generally performed after comparing multiple samples with one or more tests. An MCT will help identify a significantly different sample among multiple samples or a factor among multiple factors.
It would be easy to compare two samples using a significance alpha level of 0.05. In other words, there is only one sample pair to be compared. However, it would be difficult to identify a significantly different sample if the number...

Friedman Two-way Analysis of Variance by Ranks

Friedman Two-way Analysis of Variance by Ranks

Friedman's Two-Way Analysis of Variance by Ranks is a nonparametric test designed to identify differences across multiple test attempts when traditional assumptions of normality and equal variances do not apply. Unlike conventional ANOVA, which requires normally distributed data with equal variances, Friedman's test is ideal for ordinal or non-normally distributed data, making it particularly useful for analyzing dependent samples, such as matched subjects over time or repeated measures...

Generalized Hooke's Law

Generalized Hooke's Law

The generalized Hooke's Law is a broadened version of Hooke's Law, which extends to all types of stress and in every direction. Consider an isotropic material shaped into a cube subjected to multiaxial loading. In this scenario, normal stresses are exerted along the three coordinate axes. As a result of these stresses, the cubic shape deforms into a rectangular parallelepiped. Despite this deformation, the new shape maintains equal sides, and there is a normal strain in the direction of the...

Non-destructive Tests for Concrete Strength

Non-destructive Tests for Concrete Strength

The rebound hammer test, also known as the Schmidt hammer test, is a non-destructive technique for evaluating the hardness of concrete and, indirectly, the strength of concrete. It operates on the principle that the rebound of a spring-driven mass from a concrete surface correlates to the surface's hardness. The device comprises a mass within a tubular housing, a spring mechanism, and a plunger that strikes the concrete. Upon release, the energy imparted to the mass by the spring causes it...

Comparing Experimental Results: Student's t-Test

Comparing Experimental Results: Student's t-Test

The t-test is a statistical method used to compare the sample mean with a population mean or compare two means from two data sets. The test statistic is calculated from the standard deviation, mean, and number of measurements in the data set at a selected confidence interval and then compared to a table of critical values at this confidence level. If the test statistic is smaller than the critical value, the null hypothesis is accepted. In this case, we state that the difference between the...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Interplay between diradical character, aromaticity and conductance in oligothiophenes.

Chemical science·2026

Same author

A statistical theory of reactivity based on molecular orbitals participation and its application to organic reactions.

Physical chemistry chemical physics : PCCP·2025

Same author

Exploring Intrinsic Bond Properties with the Fukui Matrix from Conceptual Density Matrix Functional Theory.

Journal of chemical theory and computation·2025

Same author

Temperature and external fields in conceptual density functional theory.

Chemical science·2024

Same author

Slope of the Delocalization Function Is Proportional to Analytical Hardness.

The journal of physical chemistry letters·2024

Same author

Bond Lengths and Dipole Moments of Diatomic Molecules under Isotropic Pressure with the XP-PCM and GOSTSHYP Models.

Journal of chemical theory and computation·2024

Search research articles

Related Experiment Video

Updated: Jan 6, 2026

Author Spotlight: Establishing an Accurate Microhardness Testing Protocol for Craniofacial Tissues

Author Spotlight: Establishing an Accurate Microhardness Testing Protocol for Craniofacial Tissues

Published on: April 26, 2024

Analogies and differences between two ways to evaluate the global hardness.

Miquel Torrent-Sucarrat¹, Paul Geerlings

¹Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium. mtorrent@vub.ac.be

The Journal of Chemical Physics

|January 4, 2007

Summary

This summary is machine-generated.

This study analyzes energetic components of chemical properties like ionization potential and electron affinity. Contrasting finite difference and hardness kernel methods offers insights into electronic energy differentiation.

More Related Videos

Atomic Force Microscopy Cantilever-Based Nanoindentation: Mechanical Property Measurements at the Nanoscale in Air and Fluid

Atomic Force Microscopy Cantilever-Based Nanoindentation: Mechanical Property Measurements at the Nanoscale in Air and Fluid

Published on: December 2, 2022

Quantitative Hardness Measurement by Instrumented AFM-indentation

Quantitative Hardness Measurement by Instrumented AFM-indentation

Published on: November 22, 2016

Related Experiment Videos

Last Updated: Jan 6, 2026

Author Spotlight: Establishing an Accurate Microhardness Testing Protocol for Craniofacial Tissues

Author Spotlight: Establishing an Accurate Microhardness Testing Protocol for Craniofacial Tissues

Published on: April 26, 2024

Atomic Force Microscopy Cantilever-Based Nanoindentation: Mechanical Property Measurements at the Nanoscale in Air and Fluid

Atomic Force Microscopy Cantilever-Based Nanoindentation: Mechanical Property Measurements at the Nanoscale in Air and Fluid

Published on: December 2, 2022

Quantitative Hardness Measurement by Instrumented AFM-indentation

Quantitative Hardness Measurement by Instrumented AFM-indentation

Published on: November 22, 2016

Area of Science:

Quantum Chemistry
Computational Chemistry
Theoretical Chemistry

Background:

Understanding the energetic contributions to chemical properties is crucial for predicting molecular behavior.
Accurate calculation of ionization potential, electron affinity, chemical potential, and global hardness requires detailed analysis of electronic energy components.

Purpose of the Study:

To evaluate and contrast the energetic components of key chemical properties.
To compare calculated hardness terms with experimental values for a diverse set of systems.
To explore the implications of different computational approaches for understanding electronic energy.

Main Methods:

Evaluation of electronic kinetic, Coulombic, and correlation energies.
Contrast of hardness terms derived from finite difference and hardness kernel methods.
Comparison with experimental data for 40 different chemical systems.

Main Results:

The energetic components contributing to ionization potential, electron affinity, chemical potential, and global hardness were quantified.
Significant differences were observed between hardness terms calculated using finite difference and hardness kernel approaches.
The study provides a detailed comparison with experimental values across 40 systems.

Conclusions:

The contrast between finite difference and hardness kernel methods offers insights into differentiating electronic energy based on electron number or density.
This work contributes to a deeper understanding of the energetic underpinnings of chemical reactivity and stability.
The findings can guide the selection of appropriate computational methods for electronic structure calculations.