Related Experiment Video
Updated: Jun 6, 2026
06:53
Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
High-resolution Fourier spectrometry of N(2)(+)
Applied Optics
|November 19, 2010
Summary
This study analyzes spectral data of the (14)N(2)(+) ion to understand molecular interactions. New deperturbed constants reveal details of the B(2)Σ(u)(+) ~ A(2)∏(u) electronic state interaction.
Area of Science:
- Molecular Spectroscopy
- Quantum Chemistry
- Computational Physics
Background:
- The B(2)Σ(u)(+) ? X(2)Σ(g)(+) system of the (14)N(2)(+) ion is crucial for understanding molecular ion behavior.
- Perturbations between electronic states can significantly alter molecular spectra and properties.
Purpose of the Study:
- To perform a detailed perturbation analysis of the B(2)Σ(u)(+) ? X(2)Σ(g)(+) system of the (14)N(2)(+) ion.
- To derive deperturbed molecular constants and interaction parameters for the B(2)Σ(u)(+) and A(2)∏(u) states.
Main Methods:
- Spectral analysis of (14)N(2)(+) ion excited at low and high temperatures.
- Utilizing data from hollow-cathode and Pointolite lamps for excitation.
- Performing a deperturbation analysis on the B(2)Σ(u)(+) (ν = 0, ν = 1) levels.
Main Results:
- Preliminary deperturbed molecular constants for the B(2)Σ(u)(+) state have been obtained.
- Parameters characterizing the B(2)Σ(u)(+) ~ A(2)∏(u) interaction have been derived.
- The analysis provides insights into the electronic structure and interactions within the (14)N(2)(+) ion.
Conclusions:
- The perturbation analysis offers a more accurate description of the B(2)Σ(u)(+) electronic state.
- Understanding the B(2)Σ(u)(+) ~ A(2)∏(u) interaction is vital for accurate molecular modeling.
- This work contributes to the fundamental knowledge of diatomic molecular ions.
Related Concept Videos
01:12Two-Dimensional (2D) NMR: Overview
The 1D NMR spectrum of large and complex molecules like natural products has complicated splitting patterns and overlapping signals, which can be easily interpreted using 2-dimensional (2D) NMR. Unlike 1D NMR, 2D NMR has two frequency axes that provide the coupling information between the nucleus A and nucleus B in a molecule. The process from which 2D spectra are obtained has four steps.
The first step is the preparation period, during which nucleus A is excited with a radiofrequency pulse.
The first step is the preparation period, during which nucleus A is excited with a radiofrequency pulse.
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
01:10Interpreting ¹H NMR Signal Splitting: The (n + 1) Rule
In the AX proton spin system, proton A can sense the two spin states of a coupled proton X, resulting in a doublet NMR signal with two peaks of equal (1:1) intensity. When proton A is coupled to two equivalent protons (AX2 spin system), the spin states of each X can be aligned with or against the external field, creating three possible scenarios. This results in a 1:2:1 triplet signal, where the central peak corresponds to the chemical shift of A and is twice as large or intense as the others.
01:19NMR Spectroscopy Of Amines
In proton NMR spectroscopy, primary amines and secondary amines showcase their N–H protons as a broad signal in the chemical shift range between δ 0.5 and 5 ppm. The exact position in this range depends on several factors, including sample concentration, hydrogen bonding, and the type of solvent used. Since amine protons undergo fast proton exchange in solution, the protons are labile and therefore do not participate in any splitting with adjacent protons. Thus, the observed peak is broad and...
01:192D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)
Heteronuclear single-quantum correlation spectroscopy (HSQC) is a 2D NMR technique that reveals one-bond correlations between hydrogen and a heteronucleus. The HSQC experiment is similar to the heteronuclear correlation experiment (HETCOR) but is more sensitive. In the HSQC spectrum, the proton chemical shift is plotted on the horizontal F2 axis, while the 13C chemical shift is plotted on the vertical F1 axis. The corresponding proton and 13C spectra are also shown. The HSQC contour plot does...
01:08IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
Identical bonds within a polyatomic group can stretch symmetrically (in-phase) or asymmetrically (out-of-phase). Similar to hydrogen bonding, these vibrations also influence the shape of the IR peak. Generally, asymmetric stretching frequencies are higher than symmetric stretching frequencies. For example, primary amines exhibit two distinct IR peaks between 3300–3500 cm−1 corresponding to the symmetric and asymmetric N-H stretching, while secondary amines exhibit a single stretching vibration...