The BondAngles(molecule, option) calling sequence returns all of the 3-atom bond angles in the molecule as a table.  

The BondAngles(molecule, i, j, k) calling sequence returns the bond angle formed by the i, j, and k atoms in the molecule.

The BondAngles(molecule, i, j, k, l) calling sequence returns the dihedral bond angle formed by the i, j, k, and l atoms.

The BondAngles(molecule, [i,j,k]) calling sequence returns the bond angle formed by the i, j, and k atoms in the molecule.

The BondAngles(molecule, [i,j,k,l]) calling sequence returns the dihedral bond angle formed by the i, j, k, and l atoms.

The BondAngles(molecule[i], molecule[j], molecule[k]) calling sequence returns the bond angle.

The BondAngles(molecule[i], molecule[j], molecule[k], molecule[l[) calling sequence returns the dihedral bond angle.

If the optional keyword dihedral in BondAngles(molecule, option) is set to true, then all dihedral angles are also returned.  

The bond angles are returned as floats in units of degrees.

$\mathrm{with}\left(\mathrm{QuantumChemistry}\right)\:$

$\mathrm{mol}≔ \left[\left[''O''\, 0.7247\, 0\, 0\right]\, \left[''O''\, -0.7247\, 0\, 0\right]\, \left[''H''\, 0.8233\, -0.7\, -0.6676\right]\,\left[''H''\, -0.8233\, -0.6175\, 0.7446\right]\right]\;$

$\mathrm{mol}≔\left[\left[''O''\,0.72470000\,0\,0\right]\,\left[''O''\,\mathrm{-0.72470000}\,0\,0\right]\,\left[''H''\,0.82330000\,\mathrm{-0.70000000}\,\mathrm{-0.66760000}\right]\,\left[''H''\,\mathrm{-0.82330000}\,\mathrm{-0.61750000}\,0.74460000\right]\right]$

$\mathrm{output}≔ \mathrm{BondAngles}\left(\mathrm{mol}\right)\;$

$\mathrm{output}≔table\left(\left[\left(3\,1\,2\right)=\left[''a(H-O-O)''\,95.82017719\right]\,\left(4\,2\,1\right)=\left[''a(H-O-O)''\,95.82003619\right]\right]\right)$

$\mathrm{output}≔ \mathrm{BondAngles}\left(\mathrm{mol}\, \mathrm{dihedral}\=\mathrm{true}\right)\;$

$\mathrm{output}≔table\left(\left[\left(4\,2\,1\,3\right)=\left[''a(H-O-O-H)''\,93.97378730\right]\,\left(3\,1\,2\right)=\left[''a(H-O-O)''\,95.82017719\right]\,\left(4\,2\,1\right)=\left[''a(H-O-O)''\,95.82003619\right]\right]\right)$

$\mathrm{output}≔ \mathrm{BondAngles}\left(\mathrm{mol}\, 1\,2\,3\right)\;$

$\mathrm{output}≔32.00034141$

$\mathrm{output}≔ \mathrm{BondAngles}\left(\mathrm{mol}\, \left[1\,2\,3\right]\right)\;$

$\mathrm{output}≔32.00034141$

$\mathrm{output}≔ \mathrm{BondAngles}\left(\mathrm{mol}\, 1\,2\,3\,4\right)\;$

$\mathrm{output}≔89.72692682$

$\mathrm{output}≔ \mathrm{BondAngles}\left(\mathrm{mol}\, \left[1\,2\,3\,4\right]\right)\;$

$\mathrm{output}≔89.72692682$