The organic compound below, which crystallizes in the orthorhombic space group P2₁2₁2₁, can hydrogen bond through three donors: N1, N2, and O4.

The output from the HTAB instruction of SHELXL-97 includes the following: This indicates that the molecule at symmetry position #1 (x, y, z) is hydrogen-bonded to a molecule at symmetry position #3 (-x, ½ + y, ½ -z) that has then been translated by (+1, -1, +1). Add this molecule! (Click the "Help!" button for instructions). If you rotate the cell, you can see that the H on O4 is in position to form an H-bond to O5. If you double-click on those two atoms, a dotted line will be drawn.
Add the other three molecules from the SHELXL-97 output and draw in the H-bonds (it may be helpful to momentarily zoom in on the display by doing a "shift-drag" down). Finally, if you add a molecule at symmetry position #4 (the only symmetry position not mentioned above), you'll see that it is H-bonded to one of the molecules already present.

Symmetry operations (Space Group P2₁2₁2₁):

x, y, z
½ + x, ½ - y, - z
-x, ½ + y, ½ -z
½ -x, - y, ½ + z

Translations
 X:   Y:   Z:

-1 0 +1 -1 0 +1 -1 0 +1

Compound 1461

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