Water (H{sub 2}O) and nitrogen (N{sub 2}) are major detonation products of high explosives and it has long been conjectured that they may phase segregate at high enough temperatures and pressures to influence detonation properties of common explosives. We analyze the phase diagram of H{sub 2}O-N{sub 2} mixtures using a thermodynamic theory for polar-nonpolar mixtures and find that phase segregation is unlikely to occur above approximately 1600K. Therefore, H{sub 2}O-N{sub 2} immiscibility is not likely to be relevant for detonation predictions. We propose instead that the high pressure ionic dissociation of water plays an important role in detonation, and model it using a new ionic thermodynamics. We employ this model in chemical equilibrium calculations of standard high explosives, e.g. PETN, HMX and RDX, and find that it performs very well under a wide range of conditions. Thus, although it may require further development, it is likely that explicitly ionic thermodynamics will become a standard tool for explosives modeling.

Photograph of a darkly lit arched hallway in the Lee County courthouse in Giddings, Texas.

Photograph of an architectural detail on the base of the Lee County courthouse in Giddings, Texas. A red drain pipe is visible to the left.

Photograph of an arch supported by two columns near the entrance to the Lee County courthouse in Giddings, Texas. There is a red drain pipe to the immediate left of the arch, and a window is visible on the far left.

Photograph of a second floor balcony in a courtroom in the Lee County courthouse in Giddings, Texas. Lamps and a fan hang from the ceiling.

Photograph of a balcony in a courtroom in the Lee County courthouse in Giddings, Texas.

Photograph of a second floor balcony in a courtroom in the Lee County courthouse in Giddings, Texas. Several lamps and a fan hang from the ceiling.

Photograph of a base of a monument to the soldiers of the Confederate States of America on the lawn of the Bastrop County courthouse in Bastrop, Texas.

Photograph of the base of a monument to the soldiers of the Confederate States of America in front of the Bastrop County courthouse in Bastrop, Texas.

Photograph of cars in the parking lot of the Bastrop County courthouse and jail buildings in Bastrop, Texas.

Photograph of looking up at beams on a bridge over the Colorado River in Bastrop, Texas.

Photograph of a black safe door in the Lee County courthouse in Giddings, Texas.

Photograph of piles of cardboard boxes behind wrought-iron bars set in a brick building in Giddings, Texas.

Photograph of a building under construction on the corner of Main Street and Chestnut Street in Bastrop, Texas. Cars are visible on the road.

Photograph of buildings across the road in Bastrop, Texas. Cars are parked to the right, and there are lamps and trees in the foreground.

Photograph of a car waiting at a stop light in Bastrop, Texas. A building under construction is visible to the right.

Photograph of several cars parked outside the Bastrop Abstract Company building in Bastrop, Texas.

Photograph of several stacks of cardboard boxes behind wrought-iron bars on a brick building in Giddings, Texas.

Photograph of cars parked across the street from the Lee County Clerk's Office in Giddings, Texas. A white building and a church are visible in the background.

Photograph of cars driving on a street in Bastrop, Texas. Buildings are visible on both sides of the road, and a man walks on the sidewalk to the left.

Photograph of several cars in a parking lot across the street from several buildings, in Giddings, Texas.

Photograph of several cars parked on a street across from several houses, in Bastrop, Texas. There are two green lamp posts on the near side of the street.

Photograph of cars in a parking lot outside a building in Bastrop, Texas. There are green and white striped awnings above each window, and bare trees are visible to the left.

Photograph of cars parked by the side of the Calvary Episcopal Church in Bastrop, Texas.