A Classical and Pictorial Approach

The Bloch Simulator is based on the BLOCH equations, named after Felix Bloch, one of the pioneers of NMR. The underlying mathematical approach used by Bloch to understand the phenomenon of the resonance experiment was based upon the concept of 

The Bloch Simulator is used primarily to calculate and visualize the basie effects of different types of pulses and small pulse sequence fragments using a purely elassical macroscopic magnetization approach. To simplify the calculations the simulator ignores the relaxation processes that formed part of the original Bloch equations. There are three main applications for the Bloch simulator  

The simulator offers several different calculation modes designed to display a particular property of a pulse or sequence fragment in the most appropriate manner. The application of the different calculation modes is summarized below. 

There is a difference in appearance between the representation of the magnetization vectors in NMR-SIM and the classical literature approach. Because NMR-SIM is an interactive process, it is possible to simplify the display. The movement of each magnetization vector is indicated by a line drawn out on the surface of a sphere by the tip of the magnetization vector as a function of time. In the literature with a static diagram the same process would be indicated by a vector in the initial position and final positions with the movement of the magnetization vectors being denoted by dotted arrows. Fig. 4.22 shows the same pulse sequence fragment in the two different representations. 

SIM representation (left side) and the usual literature representation (right side). 

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