# q-TIP4P/F model of water

The **q-TIP4P/F** model
^{[1]}
is a flexible version of the TIP4P/2005 model of water designed for use in path integral simulations.

## Melting point[edit]

The melting point was found to be at 1 bar via direct coexistence calculations, and at 257K from calculations of the Gibbs energy function ^{[2]}.

## Isotope effects[edit]

Melting point (extract from the Ice Ih page)

(D _{2}0)Pressure Water model/technique Reference 1 bar q-TIP4P/F ^{[3]}1 bar experimental value ^{[4]}

(T _{2}0)Pressure Water model/technique Reference 1 bar q-TIP4P/F ^{[3]}0.6629 kPa experimental value ^{[5]}

It is worth pointing out that the calculations presented in the work of Ramírez and Herrero ^{[3]} used the melting point of the q-TIP4P/F model as its "reference state". It is perhaps more fruitful to examine the relative changes upon isotopic substitution: (experimental value: 3.68 K) and (experimental value: 4.49 K).

#### Ice Ih[edit]

Isotope effects have also been studied for ice Ih ^{[6]}.

## References[edit]

- ↑ Scott Habershon, Thomas E. Markland, and David E. Manolopoulos "Competing quantum effects in the dynamics of a flexible water model", Journal of Chemical Physics
**131**024501 (2009) - ↑ Scott Habershon and David E. Manolopoulos "Free energy calculations for a flexible water model", Phys. Chem. Chem. Phys.
**13**pp. 19714-19727 (2011) - ↑
^{3.0}^{3.1}^{3.2}R. Ramírez and C. P. Herrero "Quantum path integral simulation of isotope effects in the melting temperature of ice Ih", Journal of Chemical Physics 133, 144511 (2010) Cite error: Invalid`<ref>`

tag; name "Ramirez1" defined multiple times with different content Cite error: Invalid`<ref>`

tag; name "Ramirez1" defined multiple times with different content - ↑ N.N. Smirnova, T.A. Bykova, K. Van Durme and B. Van Mele "Thermodynamic properties of deuterium oxide in the temperature range from 6 to 350 K", The Journal of Chemical Thermodynamics
**38**pp. 879-883 (2006) - ↑ H. W. Xiang "Vapor Pressure and Critical Point of Tritium Oxide", Journal of Physical and Chemical Reference Data
**32**pp. 1707.1711 (2003) - ↑ Carlos P. Herrero and Rafael Ramírez "Isotope effects in ice Ih: A path-integral simulation", Journal of Chemical Physics
**134**094510 (2011)