Ascalaph Liquid

Ascalaph Liquid is a program for molecular dynamics simulation in liquid phase.

Periodic boundary conditions are used to reduce artifacts introduced by small model size and surface effects.

Water is processed in a special way. All valent parameters of the force field are ignored. Instead, the parameters of flexible SPC water from Toukan and Rahman (Phys. Rev. B, 1985, v.31, pp.2643-2648) are used.

Supercomputing on PC

In 2007, NVIDIA introduced video cards that could be used not only to show graphics but also for scientific calculations. These cards include many arithmetic units (currently up to 240) working in parallel. Long before this event, the computational power of video cards was used to accelerate calculations. What was new is that NVIDIA made it possible to develop parallel programs in a high-level language. Actually, it is the C language supplemented with several key words. This technology called CUDA substantially simplified programming by introducing the CUDA code in programs written in íà C/C++.

Ascalaph Liquid GPU is a hardware accelerated version of Ascalaph Designer, identical in all features except performance. It requires special hardware and software. The program uses an NVIDIA card to speed up the computation of non-valent interactions.

Before purchasing the program, please pay attention to the following

  1. You must have a video card supporting CUDA 2.0 technology.
  2. To achieve substantial acceleration, the video card must have at least 12 multiprocessors.
  3. Such cards consume much energy, so your computer may need a new power supply unit.
  4. You must install a driver supporting CUDA 2.0 technology.
  5. No acceleration will be observed for very small models comprising 100-200 atoms, the computation may even slow down. Substantial acceleration is achieved for models consisting of thousands of atoms.
  6. Currently the program handles medium-sized models, limited by computer configuration. Thus with 2 GB RAM and 300 MB video card memory, you can work with models including about 5000 atoms; these specifications are regarded as minimal.

 

Benchmark analysis

0.1 ps dynamics of water box.

Water molecules 512 7681536
Atoms 1536 23044608
CPU Intel Core2 Quad Q6600 @ 2.40GHz, sec 27.440.5156.5
GPU GeForce 8800 GTS (320 MB), sec 2.673.9712.3
Speedup 12.7 12.3 17.9

 

Purchase