In that study, it was emphasised that a key difference between the two crystal orientations is the effective electron mass (apart from the fact that interactions between atoms, thermomechanical response and melting are strongly affected by the interatomic distance which varies with the crystal orientation [49]); the discrepancy of the optical mass (measured or calculated in precious reports [47; 48; 50; 51; 52; 53; 54]) affects optical parameters of the material, amount of the absorbed energy and, eventually, thermal response of the system that is also projected on the type of LIPSS that are formed [46]. Nevertheless, despite these early results and conclusions, a more elaborated approach is required to evaluate more explicitly the impact of crystal orientation in the energy absorption; it is noted that TiO\({}_{2}\) is a uniaxial birefringent material with optical axis parallel to direction (001). Therefore, in the case of an irradiation under normal incidence of the face (001), the electromagnetic wave of laser propagates according to the normal refractive index \((n_{\perp},\ k_{\perp})\). On the other hand, in the case of irradiation under normal incidence of the face (100) or (110), the optical axis lies in the plane of the surface. Thus, there are waves propagating according to refractive indexes \((n_{\perp},\ k_{\perp})\) and \(\left(n_{\parallel},\ k_{\parallel}\right)\) respectively. Furthermore, although, the difference in the optical response of the system induced by the distinct crystal orientation for irradiation with femtosecond pulses has been investigated [46], no previous study has been conducted to explore the impact of the shape of the laser pulse and more specifically of temporarily separated pulses. In previous reports, the effect of the irradiation of various types of materials with temporarily separated pulses has been investigated which revealed a significant variation in the ultrafast dynamics, thermal response of the material and finally, changes in the LIPSS frequencies [29; 36; 55]. Therefore,and given the role of the crystal orientation, a detailed description of the ultrafast dynamics resulting from irradiating semiconductors with different crystal orientation with double pulses of variable temporal separation would provide significant information. More specifically, elucidation of this issue is of paramount importance, firstly, to elucidate the underlying multiscale physical mechanisms of laser-matter interaction and secondly to associate the resulting thermal effects with the induced surface patterns. To this end, we present a detailed theoretical approach that describes the ultrafast dynamics in rutile TiO\({}_{2}\)[22; 26; 56; 57; 58], to account firstly, for excitation and electron-phonon relaxation upon irradiation of TiO\({}_{2}\) in two crystal orientations with periodic ultrashort laser double-pulses separated by a temporal delay from zero to tens of picoseconds (Section 2). The details of an experimental protocol that has been developed is described in Section 3, while a thorough analysis of results and validation of the theoretical model are presented in Section 4 by discussing the ultrafast dynamics, thermal response and induced surface modification predictions. Concluding remarks follow in Section 5.