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
  1. Home
  3. Research Domains
  1. Home
  3. Research Domains

Related Concept Videos

Aromatic Hydrocarbon Cations: Structural Overview01:18

Aromatic Hydrocarbon Cations: Structural Overview

2.8K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
2.8K
Aromatic Hydrocarbon Anions: Structural Overview01:18

Aromatic Hydrocarbon Anions: Structural Overview

2.8K
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous...
2.8K
π Molecular Orbitals of 1,3-Butadiene01:24

π Molecular Orbitals of 1,3-Butadiene

9.0K
Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
9.0K
Frost Circles for Different Conjugated Systems01:18

Frost Circles for Different Conjugated Systems

2.7K
The inscribed polygon method is consistent with Hückel’s 4n + 2 rule and helps to learn whether the given cyclic compound is aromatic or not. The compound is stable and aromatic if every bonding molecular orbital (MO) is completely filled with a pair of electrons. However, if the non-bonding or antibonding orbitals are filled with electrons, the compound is unstable and not aromatic. Consider the Frost circle diagrams for cycloalkenes containing 4 to 8 carbons.
2.7K
Exceptions to the Octet Rule02:55

Exceptions to the Octet Rule

28.2K
Many covalent molecules have central atoms that do not have eight electrons in their Lewis structures. These molecules fall into three categories:
28.2K
The Aufbau Principle and Hund's Rule03:02

The Aufbau Principle and Hund's Rule

48.6K
To determine the electron configuration for any particular atom, we can build the structures in the order of atomic numbers. Beginning with hydrogen, and continuing across the periods of the periodic table, we add one proton at a time to the nucleus and one electron to the proper subshell until we have described the electron configurations of all the elements. This procedure is called the aufbau principle, from the German word aufbau (“to build up”). Each added electron occupies the...
48.6K
  • Physical Sciences
  • Condensed Matter Physics
  • Surface Properties Of Condensed Matter
  • Valence Shell Electronically Excited States Of Norbornadiene And Quadricyclane.
  • Physical Sciences
  • Condensed Matter Physics
  • Surface Properties Of Condensed Matter
  • Valence Shell Electronically Excited States Of Norbornadiene And Quadricyclane.

    • Related Experiment Video

    A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
    09:08

    A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

    Published on: February 27, 2017

    10.4K

    Valence shell electronically excited states of norbornadiene and quadricyclane.

    Joseph C Cooper1, David M P Holland2, Rebecca A Ingle3

    • 1Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3QZ, United Kingdom.

    The Journal of Chemical Physics
    |February 13, 2024

    View abstract on PubMed

    Summary
    This summary is machine-generated.

    Photoabsorption cross sections of norbornadiene (NBD) and quadricyclane (QC) were measured up to 10.8 eV. This study revises previous assignments for NBD and proposes new ones for QC, aiding solar energy storage research.

    More Related Videos

    Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
    10:44

    Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

    Published on: April 19, 2019

    10.8K
    Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
    11:44

    Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds

    Published on: October 18, 2018

    26.5K

    Related Experiment Videos

    A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
    09:08

    A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

    Published on: February 27, 2017

    10.4K
    Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
    10:44

    Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

    Published on: April 19, 2019

    10.8K
    Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
    11:44

    Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds

    Published on: October 18, 2018

    26.5K

    Area of Science:

    • Physical Chemistry
    • Spectroscopy
    • Materials Science

    Background:

    • Norbornadiene (NBD) and quadricyclane (QC) are isomers of C7H8 with potential in solar energy storage.
    • Understanding their electronic structure and excitation pathways is crucial for optimizing their application.

    Purpose of the Study:

    • To measure and analyze the absolute photoabsorption cross sections of NBD and QC.
    • To assign electronic transitions and revise previous interpretations of their absorption spectra.
    • To investigate the Rydberg and valence character of excited states.

    Main Methods:

    • Photoabsorption cross section measurements using Fourier transform spectroscopy at the SOLEIL synchrotron.
    • Calculation of vertical transition energies and oscillator strengths.
    • Franck-Condon and Herzberg-Teller modeling for vibrational structure analysis.
    • Natural transition orbital analysis.

    Main Results:

    • Measured photoabsorption cross sections for NBD and QC from threshold to 10.8 eV.
    • Identified sharp structures attributed to Rydberg states and broad bands to valence excitations.
    • Revised vibrational assignments and band origins for NBD, including its adiabatic first ionization energy.
    • Proposed tentative assignments for complex absorption bands in QC (5.4–7.0 eV).

    Conclusions:

    • The study provides detailed photoabsorption spectra and assignments for NBD and QC.
    • Excited states in NBD show mixed Rydberg/valence character, while QC's initial excited states are predominantly Rydberg.
    • Revised spectral assignments enhance understanding for solar energy storage applications.