Chemical exchange

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Contents 1 Chemical Exchange 2 Introduction 3 Fast Exchange 4 Intermediate Exchange 5 Slow Exhange

Chemical Exchange

Introduction

Chemical exchange for NMR processes can be classed into three major groups: fast exchange, intermediate exchange and slow exchange. In the equations below k is the exchange rate, and Ω (omega; majuscule ) is the difference of the rotating frame frequency (ω (rotating frame) ;minuscule) from the Larmor frequencey (ω0). Ω is simply then [ω_0]

Fast Exchange

Fast exchange: k >>|Ω1-Ω2|-The exchange rate is much greater than difference of resonance peak positions.

Intermediate Exchange

Intermediate exchange: k ~|Ω1-Ω2|-The exchange rate is approximately equal to the difference in resonance peak positions.

Slow Exhange

Slow exchange: k << |Ω1-Ω2|-The exchange rate is much less than the different resonance location.