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

Reflection of Waves

Reflection of Waves

When a wave travels from one medium to another, it gets reflected at the boundary of the second medium. A common example of this is when a person yells at a distance from a cliff and hears the echo of their voice. The sound waves (longitudinal waves) traveling in the air are reflected from the bounding cliff. Similarly, flipping one end of a string whose other end is tied to a wall causes a pulse (transverse wave) to travel through the string, which gets reflected upon reaching the wall. In...

Reflective Property of Parabolas

Reflective Property of Parabolas

A parabola is a basic type of conic section that results from the intersection of a plane with a double-napped cone in a direction parallel to one of the cone's sides. This U-shaped curve has a distinctive reflective property: all incoming rays parallel to its axis of symmetry are directed toward a single point, known as the focus. This property is widely utilized in optical and communication technologies that require precise signal concentration.In analytic geometry, a parabola is defined as...

Conditions of Equilibrium

Conditions of Equilibrium

Equilibrium refers to a state where a rigid body is not subjected to any translational or rotational motion. This state is achieved when the force and couple acting on a rigid body equal zero. When the system of external forces results in a net effect equivalent to zero, the rigid body is considered to be in equilibrium.
Internal forces are not considered for conditions of equilibrium because they occur in equal and opposite pairs within the body, effectively canceling each other. As a result,...

Magnetostatic Boundary Conditions

Magnetostatic Boundary Conditions

An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...

Woodward–Hoffmann Selection Rules and Microscopic Reversibility

Woodward–Hoffmann Selection Rules and Microscopic Reversibility

Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...

Total Internal Reflection Fluorescence Microscopy

Total Internal Reflection Fluorescence Microscopy

Total internal reflection fluorescence microscopy or TIRF is an advanced microscopic technique used to visualize fluorophores in samples close to a solid surface with a higher refractive index, such as a glass coverslip. TIRF only allows fluorophores in proximity to the solid surface to be excited. When light from a medium with a lower refractive index (such as air) hits the glass coverslip at a critical angle, the light undergoes total internal reflection stead of passing through the glass.

You might also read

Related Articles

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

Sort by

Same author

Superparamagnetic hybrid micelles, based on iron oxide nanoparticles and well-defined diblock copolymers possessing beta-ketoester functionalities.

Biomacromolecules·2009

Same journal

Report of the Executive Committee for 2006.

Acta crystallographica. Section A, Foundations of crystallography·2020

Same journal

Spin line groups.

Acta crystallographica. Section A, Foundations of crystallography·2013

Same journal

Distribution rules of systematic absences on the Conway topograph and their application to powder auto-indexing.

Acta crystallographica. Section A, Foundations of crystallography·2013

Same journal

Platonic solids generate their four-dimensional analogues.

Acta crystallographica. Section A, Foundations of crystallography·2013

Same journal

C70, C80, C90 and carbon nanotubes by breaking of the icosahedral symmetry of C60.

Acta crystallographica. Section A, Foundations of crystallography·2013

Same journal

Comparative study of X-ray charge-density data on CoSb3.

Acta crystallographica. Section A, Foundations of crystallography·2013

See all related articles

Search research articles

Related Experiment Video

Updated: Jun 2, 2026

Using Three-color Single-molecule FRET to Study the Correlation of Protein Interactions

Using Three-color Single-molecule FRET to Study the Correlation of Protein Interactions

Published on: January 30, 2018

Pseudo extra reflection conditions.

Nicolae C Popa¹

¹National Institute of Materials Physics, Ilfov, Romania. nicpopa@infim.ro

Acta Crystallographica. Section A, Foundations of Crystallography

|April 14, 2011

Summary

This summary is machine-generated.

Anisotropic atomic vibrations and disorder can cause violations of extra reflection conditions in crystallography. This study inventories these

More Related Videos

Recording Behavioral Responses to Reflection in Crayfish

Recording Behavioral Responses to Reflection in Crayfish

Published on: May 14, 2010

Related Experiment Videos

Last Updated: Jun 2, 2026

Using Three-color Single-molecule FRET to Study the Correlation of Protein Interactions

Using Three-color Single-molecule FRET to Study the Correlation of Protein Interactions

Published on: January 30, 2018

Recording Behavioral Responses to Reflection in Crayfish

Recording Behavioral Responses to Reflection in Crayfish

Published on: May 14, 2010

Area of Science:

Crystallography
Materials Science
Solid-State Chemistry

Background:

Extra reflection conditions are fundamental in crystallography for determining space groups.
These conditions assume isotropic atomic vibrations and disorder, which is not always true.
Anisotropic atomic motion can lead to measurable intensities for reflections that should be absent.

Purpose of the Study:

To identify and catalog 'pseudo extra reflection conditions' across all space groups.
To provide a resource for early-stage crystallographic structure investigations.
To understand the impact of anisotropic atomic vibrations and disorder on crystallographic data.

Main Methods:

Systematic analysis of crystallographic reflection conditions.
Examination of the effects of anisotropic atomic displacement parameters.
Demonstration with four specific crystallographic examples.

Main Results:

Identified numerous 'pseudo extra reflection conditions' that can violate systematic absences.
Quantified the influence of thermal vibrations and positional disorder on reflection intensities.
Developed a framework for predicting the status of many extra reflection conditions.

Conclusions:

Anisotropy in atomic motion necessitates careful consideration of extra reflection conditions.
The inventory of pseudo extra reflection conditions aids in accurate structure determination.
Predictive methods can streamline the analysis of crystallographic data, especially in complex cases.