The Effects of Long Pulse Durations and Radiation Damping in Selective Inversion Recovery Experiments

TL;DR

This paper investigates how long pulse durations and radiation damping affect the accuracy of selective inversion recovery experiments in NMR, highlighting the need for careful parameter selection to ensure reliable measurements.

Contribution

It demonstrates the impact of long pulses and radiation damping on SIR experiments and emphasizes the importance of understanding magnetization evolution for accurate quantitative NMR.

Findings

Long pulse durations and radiation damping cause inaccuracies in SIR experiments.

These effects complicate measurements in simple and complex spin systems.

Proper experimental parameter selection is crucial for reliable results.

Abstract

Long pulse durations necessary in selective inversion recovery (SIR) experiments along with radiation damping (RD) introduce difficulties in quantitative nuclear magnetic resonance measurements, such as those that allow for the determination of a sample's characteristics, including the rates that govern magnetization transfer. Because of these influences, the assumption of perfect inversion is invalid. In this work, we present data that demonstrates that long pulse durations as well as RD cause difficulties in SIR experiments performed on simple one-spin systems, indicating that they will be problematic for multiple-spin systems as well. These results emphasize the importance of understanding the evolution of magnetization for all time points throughout an experiment used in quantitative NMR measurements. Furthermore, experimental parameters must be chosen carefully and understood completely.