e crystal and magnetic order: * epsilon_T:  crystal chirality, in our case we select J3-J5 interactions according to the chirality (J5&gt;J3). * epsilon_Delta: Chirality of the triangular units. * epsilon_H: Sense of rotation of the spin helices along the c-axis (right handed rotation is positive). The three property are related: eT = eD*eH.</p><pre class="codeinput">eD = -1;
eH = +1;
eT = eD*eH;
</pre><h2 id="3">Magnetic Hamiltonian</h2><p>We define the magnetic Hamiltonian depending on the epsilon_T cryst