Nodes of the superconducting gap probed by electronic Raman scattering   in HgBa_{2}CaCu_{2}O_{6+\delta } single crystals
  Pure electronic Raman spectra with no phonon structures superimposed to the electronic continuum, are reported, in optimally doped HgBa_{2}CaCu_{2}O_{6+\delta } single crystals (T_{c }=126 K). As a consequence, the spectra in the A_{1g }, B_{1g } and B_{2g } symmetries, including the crucial low energy frequency dependence of the electronic scattering, are directly and reliably measured. The B_{2g } and, most strikingly, the B_{1g } spectra exhibit a strong intrinsic linear term, which suggests that the nodes are shifted from the [110] and [1\bar{1}0] directions, a result inconsistent with a pure d_{x^{2}-y^{2}} model. 
A. Sacuto, R. Combescot, N. Bontemps, P. Monod, V. Viallet and D.   Colson