An octahedron and its four quarters

An octahedron can be decomposed into four non regular tetrahedra, whose net is composed of two equilateral triangles and two isosceles rectangular triangles (a square folded along its diagonal).

If the edges of the octahedron is 1, what are the sides of this non regular tetrahedron?

1 [math]\frac{\sqrt{3}}{2}[/math] [math]\frac{\sqrt{2}}{2}[/math] [math]\frac{1}{\sqrt{2}}[/math] 2 [math]\sqrt{2}[/math]

Information: An octahedron and its four quarters