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

Crystal Field Theory - Octahedral Complexes02:58

Crystal Field Theory - Octahedral Complexes

29.6K
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...
29.6K
Structure of Amines01:19

Structure of Amines

3.0K
The hybridized nitrogen atom in amines possesses a lone pair of electrons and is bound to three substituents with a bond angle of around 108°, which is less than the tetrahedral angle of 109.5°. However, the C–N–H bond angle is slightly larger at 112°, with a carbon–nitrogen bond length of 147 pm. This carbon–nitrogen bond length of of amines is longer than the carbon–oxygen bond of alcohols (143 pm) but shorter than alkanes’ carbon–carbon bond (154 pm). These aspects are...
3.0K
Crystal Field Theory - Tetrahedral and Square Planar Complexes02:46

Crystal Field Theory - Tetrahedral and Square Planar Complexes

46.9K
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,...
46.9K
Structures of Solids02:22

Structures of Solids

17.1K
Solids in which the atoms, ions, or molecules are arranged in a definite repeating pattern are known as crystalline solids. Metals and ionic compounds typically form ordered, crystalline solids. A crystalline solid has a precise melting temperature because each atom or molecule of the same type is held in place with the same forces or energy. Amorphous solids or non-crystalline solids (or, sometimes, glasses) which lack an ordered internal structure and are randomly arranged. Substances that...
17.1K
Molecular and Ionic Solids02:54

Molecular and Ionic Solids

19.5K
Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their interparticle interactions.
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
19.5K
Ionic Crystal Structures02:42

Ionic Crystal Structures

16.4K
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...
16.4K

You might also read

Related Articles

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

Sort by
Same author

Biofilm Formation in Indwelling Percutaneous Nephrostomy Catheters: Luminal Loss and Bacterial Colonization.

Interventional radiology (Higashimatsuyama-shi (Japan)·2026
Same author

Experiences of LGBTQ+ Primary Care Clinicians Providing Care for Lesbian, Gay, Bisexual, Transgender and Queer People: An Interpretative Phenomenological Analysis.

Journal of clinical nursing·2026
Same author

Spontaneously polarised crystalline water ice.

Nanoscale·2026
Same author

Outcome after Selective early treatment for Closure of patent ductus ARteriosus in preterm babies, a multicentre, masked, randomised placebo-controlled parallel group trial (Baby-OSCAR trial).

Health technology assessment (Winchester, England)·2026
Same author

Corrigendum to 'Two-year outcomes after selective early treatment of patent ductus arteriosus with ibuprofen in preterm babies: follow-up of Baby-OSCAR-a randomised controlled trial' [eClinicalMedicine, Volume 87, September 2025, 103424].

EClinicalMedicine·2026
Same author

Formation and oxygen intercalation of vitreous 2D silica bilayer films on Ir(111).

Physical chemistry chemical physics : PCCP·2026
Same journal

Monthly Energy, Exergy, Environmental, and Economic Performance and Green Hydrogen Production Analysis of a Flat-Plate Solar Collector-Driven Organic Rankine Cycle System Under Variable Mass Flow and Irradiance.

ChemistryOpen·2026
Same journal

The Versatile Structural World of Methanedi- and Trisulfonic Acid and Their Salts.

ChemistryOpen·2026
Same journal

The Role of Conformational Preorganization in the Reactivity of cis-1,2-Dimesylate-bis(benzyloxy)cyclooctane: An Activation Strain Perspective.

ChemistryOpen·2026
Same journal

Epoxy Clerodane Diterpene Attenuates the Differentiated Adipocyte Hypertrophy and Enhances Mitochondrial Metabolism.

ChemistryOpen·2026
Same journal

Magnetic Nickel-Containing Heterogeneous Catalysts for the Heck Reaction: Catalyst Design, Performance, and Sustainability.

ChemistryOpen·2026
Same journal

First-Principles Design of Room Temperature Ferromagnetic Metallic Rare-Earth Zintl Compounds AB<sub>2</sub>C<sub>2</sub> (A = Ce, Pr, Nd; B = Li; C = Sb) for Next-Generation Spintronic and Magneto-Electronic Applications.

ChemistryOpen·2026
See all related articles

Related Experiment Video

Updated: Dec 6, 2025

Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia
12:05

Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia

Published on: October 10, 2013

15.9K

Crystallites and Electric Fields in Solid Ammonia.

Andrew Cassidy1, Rachel L James2, Anita Dawes2

  • 1Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000, Aarhus, Denmark.

Chemistryopen
|October 7, 2020
PubMed
Summary
This summary is machine-generated.

Solid ammonia exhibits polymorphism, with distinct phases identified through optical absorption spectra. These spectral shifts reveal spontaneously generated electric fields and provide quantitative insights into crystallite size and molecular packing in ammonia films.

Keywords:
Wannier-Mott excitonammoniamolecular icespolarised solidsspectroscopy

More Related Videos

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
06:35

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates

Published on: February 15, 2016

8.4K
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
08:55

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Published on: June 7, 2018

8.8K

Related Experiment Videos

Last Updated: Dec 6, 2025

Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia
12:05

Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia

Published on: October 10, 2013

15.9K
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
06:35

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates

Published on: February 15, 2016

8.4K
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
08:55

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Published on: June 7, 2018

8.8K

Area of Science:

  • Solid-state physics
  • Materials science
  • Spectroscopy

Background:

  • Ammonia (NH3) is a fundamental molecule with applications in various scientific fields.
  • Understanding the solid phases of ammonia is crucial for astrophysical and chemical contexts.
  • Previous studies have explored ammonia's properties, but detailed optical characterization of its solid phases remains an area of interest.

Purpose of the Study:

  • To investigate the optical absorption spectra of vacuum-deposited ammonia films.
  • To identify different solid phases of ammonia and their characteristics.
  • To determine the influence of deposition temperature on ammonia film properties, including electric fields and crystallite size.

Main Methods:

  • Obtained absorption spectra of ammonia films in the ultraviolet range (115–310 nm).
  • Varied deposition temperatures (Td) between 20 K and 80 K to study phase transitions.
  • Analyzed Rydberg transitions and Wannier-Mott excitons to probe film structure.

Main Results:

  • Identified two distinct solid phases of ammonia, indicating polymorphism.
  • Observed significant red shifts in absorption peaks with increasing deposition temperature, correlating with spontaneously generated electric fields.
  • Quantified crystallite sizes and molecular content within these phases, providing a more precise description than 'amorphous'.

Conclusions:

  • Solid ammonia is polymorphic, with distinct optical properties for different phases.
  • Spontaneously generated electric fields, exceeding 10^8 V/m, are present in low-temperature ammonia films.
  • The study provides quantitative data on crystallite size and molecular packing in solid ammonia films.