The proposed experiment aims to explore in detail these two effects in a thermodynamic range at ~25 MPa over a temperature range of 280° to 600°C, never investigated before, where the system undergoes different degrees of hydrogen bonding. This proposal is part of a series of experiments (DINS and INS) and Monte Carlo simulation aiming to characterize the molecular dynamics of supercritical water across the pseudo-critical temperature in an extended thermodynamic region never investigated before, under the conditions pertinent to the proposed operation of supercritical water-cooled reactors (SCWRs). DINS results will be also a challenge to theoretical models that attempt to describe this phase. For supercritical water unique thermodynamic properties SCWR is considered a promising candidate of advanced power reactors that belong to the so-called the Generation-IV reactor technology.