# ThreeJSymbol

ThreeJSymbol[{j1,m1},{j2,m2},{j3,m3}]

gives the values of the Wigner 3 symbol.

# Details • The 3 symbols vanish except when and the satisfy a triangle inequality.
• The parameters of ThreeJSymbol can be integers, halfintegers or symbolic expressions.
• The ClebschGordan coefficients and 3 symbols in the Wolfram Language satisfy the relation .

# Examples

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## Basic Examples(2)

Use symbolic arguments to obtain exact symbolic answers:

## Scope(2)

ThreeJSymbol works with integer and halfinteger arguments:

## Applications(3)

Plot 3 symbol coefficients as a function of and :

Apply angular momentum operators to spherical harmonics:

Evaluate Gaunt coefficients:

Evaluate an explicit triple integral of spherical harmonics:

## Properties & Relations(4)

Evaluate the completely symbolic case of ThreeJSymbol:

Demonstrate sum orthogonality:

Convert to a Regge R symbol:

Check the symmetry of the Regge R symbol:

Compare with sum definition:

## Possible Issues(1)

A message is issued and the result 0 returned in the case : Introduced in 1991
(2.0)