Related Experiment Video
Updated: Jul 8, 2026

Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
Pippard relations applied to the lambda-phase transition in NH4Br
1Department of Physics, Middle East Technical University, 06531 Ankara, Turkey. hamit@metu.edu.tr
Abstract:
We establish here a linear variation of the specific heat C(P) with the frequency shifts (1/nu)(partial differential nu/partial differential T)P close to the lambda-phase transition in NH4Br (Tlambda = 234 K). This linear relationship is based on our spectroscopically modified Pippard relations. For this verification of our relations, we use our observed Raman frequencies of the lattice mode of nu7 (56 cm(-1)) and the internal mode of nu2 (1684 cm(-1)) in the NH4Br crystalline system. Our study given here indicates that the thermodynamic data can be obtained from the measured frequencies.
Related Concept Videos
¹H NMR: Complex Splitting
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
VSEPR Theory and the Effect of Lone Pairs
¹H NMR: Pople Notation
A proton...
Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility
Temporary attractive forces like dispersion are present in all molecules, whether they are polar or nonpolar. They...
Inductive Effects on Chemical Shift: Overview

