Signs and General Magnitudes of K XY

The signs and magnitudes of coupling constants are determined by structural factors to a significant extent, and we will consider them in the three sections following this one. However, there are global, Periodic-Table-wide trends that should be noted and are treated in this section. 

References and notes for this table are given in Table 2. 

Trends in Magnitudes of the One-Bond Coupling down a Family of the Periodic Table and along a Row 

There is a wide variation in magnitudes of one-bond coupling constants, some part of which is due to the wide range of magnetogyric ratios. We eliminate this by 

The only experimental value available is that for The sign was determined by a molecular 

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