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

Hess's Law

Hess's Law

There are two ways to determine the amount of heat involved in a chemical change: measure it experimentally, or calculate it from other experimentally determined enthalpy changes. Some reactions are difficult, if not impossible, to investigate and make accurate measurements for experimentally. And even when a reaction is not hard to perform or measure, it is convenient to be able to determine the heat involved in a reaction without having to perform an experiment.

Mixtures of Acids

Mixtures of Acids

The pH of a solution containing an acid can be determined using its acid dissociation constant and initial concentration. If a solution contains two different acids, then its pH can be determined using one of several methods depending on the relative strength of the acids and their dissociation constants.
In a strong and weak acid mixture, the strong acid dissociates completely and becomes a source of almost all the hydronium ions present in the solution. In contrast, the weak acid shows...

Polyprotic Acids

Polyprotic Acids

Acids are classified by the number of protons per molecule that they can give up in a reaction. Acids such as HCl, HNO3, and HCN that contain one ionizable hydrogen atom in each molecule are called monoprotic acids. Their reactions with water are:

Calculating pH Changes in a Buffer Solution

Calculating pH Changes in a Buffer Solution

A buffer can prevent a sudden drop or increase in the pH of a solution after the addition of a strong acid or base up to its buffering capacity; however, such addition of a strong acid or base does result in the slight pH change of the solution. The small pH change can be calculated by determining the resulting change in the concentration of buffer components, i.e., a weak acid and its conjugate base or vice versa. The concentrations obtained using these stoichiometric calculations can be used...

Column Efficiency: Plate Theory

Column Efficiency: Plate Theory

Band broadening in a chromatography column is measured by its efficiency. This is determined by the number of theoretical plates (N). Theoretical plate theory states that a separation column consists of a continuous series of imaginary plates where solute equilibration occurs between stationary and mobile phases.
A higher number of theoretical plates signifies better column efficiency and improved separation capabilities. Plate height affects bandwidth and separation quality; it is inversely...

Testing a Claim about Standard Deviation

Testing a Claim about Standard Deviation

A complete procedure to test a claim about population standard deviation or population variance is explained here.
The hypothesis testing for the claim of population standard deviation (or variance) requires the data and samples to be random and unbiased. The population distribution also must be normal. There is no specific requirement on the sample size as the estimation is based on the chi-square distribution.
As a first step, the hypothesis (null and alternative) concerning the claim about...

You might also read

Related Articles

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

Sort by

Same author

Enhancing the efficiency of time-dependent density functional theory calculations of dynamic response properties.

npj computational materials·2026

Same author

Machine Learning-Enhanced Orbital-Free Density Functional Theory.

Journal of chemical theory and computation·2026

Same author

Learning the One-Electron Reduced Density Matrix at SCF Convergence Thresholds.

Journal of chemical theory and computation·2025

Same author

Density-Functionalized QM/MM Delivers Chemical Accuracy For Solvated Systems.

Journal of chemical theory and computation·2025

Same author

Theoretical Studies of Non-Metal Endohedral Fullerenes.

Nanomaterials (Basel, Switzerland)·2025

Same author

Rothe Time Propagation for Coupled Electronic and Rovibrational Quantum Dynamics.

The journal of physical chemistry. A·2025

Search research articles

Related Experiment Video

Updated: Jun 18, 2026

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Published on: March 29, 2016

How to calculate H3 better.

Michele Pavanello¹, Wei-Cheng Tung, Ludwik Adamowicz

¹Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA. pavanell@email.arizona.edu

The Journal of Chemical Physics

|November 18, 2009

Summary

This study introduces a novel method for systematically expanding basis sets in variational calculations. The approach achieves highly accurate results for molecular systems, demonstrated by precise energy calculations for H(3).

Area of Science:

Computational chemistry
Quantum mechanics
Molecular modeling

Background:

Accurate variational calculations of molecular systems require efficient basis set optimization.
Explicitly correlated functions dependent on interelectron distances are crucial for high accuracy.

Purpose of the Study:

To present a systematic method for enlarging basis sets of explicitly correlated functions.
To demonstrate the method's performance in variational calculations.

Main Methods:

Utilizing the iterative-complement-interaction approach.
Employing explicitly correlated Gaussian functions with shifted centers.
Systematic basis set enlargement for variational calculations.

Main Results:

More Related Videos

Defining Hsp33's Redox-regulated Chaperone Activity and Mapping Conformational Changes on Hsp33 Using Hydrogen-deuterium Exchange Mass Spectrometry

Defining Hsp33's Redox-regulated Chaperone Activity and Mapping Conformational Changes on Hsp33 Using Hydrogen-deuterium Exchange Mass Spectrometry

Published on: June 7, 2018

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

Published on: July 10, 2015

Related Experiment Videos

Last Updated: Jun 18, 2026

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Published on: March 29, 2016

Defining Hsp33's Redox-regulated Chaperone Activity and Mapping Conformational Changes on Hsp33 Using Hydrogen-deuterium Exchange Mass Spectrometry

Defining Hsp33's Redox-regulated Chaperone Activity and Mapping Conformational Changes on Hsp33 Using Hydrogen-deuterium Exchange Mass Spectrometry

Published on: June 7, 2018

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

Published on: July 10, 2015

Achieved the most accurate variational energy (-1.674 547 421 Hartree) for H(3) to date.
Obtained the most accurate binding energy (-15.74 cm(-1)) for H(3) using 1000 Gaussians.
Demonstrated the effectiveness of the iterative-complement-interaction approach.

Conclusions:

The presented method enables efficient and systematic basis set optimization.
This approach significantly enhances accuracy in variational calculations of molecular systems.
The findings set a new benchmark for H(3) energy and binding energy calculations.