Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Ionic Crystal Structures02:42

Ionic Crystal Structures

Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Crystal Field Theory - Tetrahedral and Square Planar Complexes02:46

Crystal Field Theory - Tetrahedral and Square Planar Complexes

Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal Field Theory - Octahedral Complexes02:58

Crystal Field Theory - Octahedral Complexes

Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Molecular Shapes01:18

Molecular Shapes

Molecules have characteristic shapes that are crucial for their function. The arrangement of various electron groups around the central atom dictates their molecular geometry. Electron pairs in the valence shell of a central atom will adopt an arrangement that minimizes repulsions between the electron pairs by maximizing the distance between them. The valence electrons form either bonding pairs, located primarily between bonded atoms, or lone pairs.Two regions of electron density in a diatomic...
Predicting Molecular Geometry02:27

Predicting Molecular Geometry

VSEPR Theory for Determination of Electron Pair Geometries
VSEPR Theory02:37

VSEPR Theory

Valence shell electron-pair repulsion theory (VSEPR theory) enables us to predict the molecular structure around a central atom from an examination of the number of bonds and lone electron pairs in its Lewis structure. The VSEPR model assumes that electron pairs in the valence shell of a central atom will adopt an arrangement that minimizes repulsions between these electron pairs by maximizing the distance between them. The electrons in the valence shell of a central atom form either bonding...

You might also read

Related Articles

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

Sort by
Same author

Recent Synthesis Routes to Previously Inaccessible Zeolite Porosity: From Ultrasmall Pore to Ultraporous Materials.

ACS applied materials & interfaces·2026
Same author

Decoding multidimensional regulatory networks in <i>Streptomyces</i> to accelerate natural product discovery and production.

Natural product reports·2026
Same author

Seizure following epidural blood patch in spontaneous intracranial hypotension complicated by subdural hematoma: Illustrated case and literature review.

Surgical neurology international·2026
Same author

Factors related to unmet nursing care needs for home-visit nursing among long-term care insurance beneficiaries.

Geriatric nursing (New York, N.Y.)·2026
Same author

Pressure-Induced Structural, Mechanical, and Optoelectronic Tunability in Fluorinated Two-Dimensional Hybrid Perovskite (FPMA)<sub>2</sub>PbI<sub>4</sub>.

The journal of physical chemistry letters·2026
Same author

Lessons from Failed Attempts of Computationally Guided Synthesis of Aluminosilicate STF and IFR Zeolites in Hydroxide Media.

Chemistry of materials : a publication of the American Chemical Society·2025

Related Experiment Video

Updated: Jun 1, 2026

Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route
08:26

Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route

Published on: April 3, 2016

Tetrahedral atom ordering in a zeolite framework: a key factor affecting its physicochemical properties.

Jiho Shin1, Deu S Bhange, Miguel A Camblor

  • 1School of Environmental Science and Engineering and Department of Chemical Engineering, POSTECH, Pohang 790-784, Korea.

Journal of the American Chemical Society
|June 4, 2011
PubMed
Summary

Cation exchange in gallosilicate natrolites is surprisingly flexible. Zeolite pore size dynamically adjusts, allowing larger cations to pass, especially in disordered structures, revealing a novel flexibility mechanism.

More Related Videos

Organic Structure-directing Agent-free Synthesis for *BEA-type Zeolite Membrane
08:49

Organic Structure-directing Agent-free Synthesis for *BEA-type Zeolite Membrane

Published on: February 22, 2020

Experimental Strategies to Bridge Large Tissue Gaps in the Injured Spinal Cord after Acute and Chronic Lesion
09:14

Experimental Strategies to Bridge Large Tissue Gaps in the Injured Spinal Cord after Acute and Chronic Lesion

Published on: April 5, 2016

Related Experiment Videos

Last Updated: Jun 1, 2026

Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route
08:26

Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route

Published on: April 3, 2016

Organic Structure-directing Agent-free Synthesis for *BEA-type Zeolite Membrane
08:49

Organic Structure-directing Agent-free Synthesis for *BEA-type Zeolite Membrane

Published on: February 22, 2020

Experimental Strategies to Bridge Large Tissue Gaps in the Injured Spinal Cord after Acute and Chronic Lesion
09:14

Experimental Strategies to Bridge Large Tissue Gaps in the Injured Spinal Cord after Acute and Chronic Lesion

Published on: April 5, 2016

Area of Science:

  • Materials Science
  • Inorganic Chemistry
  • Crystallography

Background:

  • Gällosilicate natrolites exhibit varying cation exchange capabilities despite similar chemical compositions.
  • The distribution of silicon (Si) and gallium (Ga) over tetrahedral sites (T-sites) influences cation exchange performance.
  • Cation exchange ability decreases with increasing cation size and T-atom ordering.

Purpose of the Study:

  • To investigate the structural basis for differing cation exchange performance in gallosilicate natrolites.
  • To understand the role of T-atom ordering and framework flexibility in cation transport.
  • To elucidate the mechanism behind cation passage through pores smaller than the cations themselves.

Main Methods:

  • Refinement of crystal structures for 11 different zeolites using synchrotron diffraction data.
  • Characterization of three sodium gallosilicate natrolites with varying degrees of T-atom ordering (low, medium, high).
  • Analysis of cation exchange performance with alkali metal cations (Na+, K+, Cs+).

Main Results:

  • Crystallographic pore sizes are generally smaller than larger alkali cations, yet exchange occurs.
  • Significant pore deformation dynamically opens pathways for cation traffic, particularly in disordered structures.
  • Back-exchange experiments on dehydrated K+ forms show Na+ passage despite crystallographically small pores.

Conclusions:

  • Gallosilicate natrolites exhibit significant topological and chain flexibility, enabling dynamic pore opening for cation exchange.
  • The degree of T-atom ordering and preferential Si/Ga siting on T-sites are hypothesized to influence framework rigidity.
  • Dynamic pore deformation is a key mechanism allowing cation transport beyond static crystallographic constraints.