HaptiChem is an educational and research tool for virtually feeling molecular interactions by combining visualization and haptic technologies . The concept of the system is to provide virtual experience of touching molecules and feeling the force between them to help learner to get image and to grasp the concept of molecules, which is the most fundamental issue in chemistry. The user can move one of the molecules in the 3D space by using the 3D mouse, while physically feeling the intermolecular force in the distance between the molecules. User can recognize the physicochemical parameters and the magnitude of the forces displayed on the 3D mouse at the same time. The haptic device used here is called SPIDAR-G [36] (Figure ), which was developed by Sato et al. This is a tension based 7-DOF force feedback device with a sphere grip. The current shape of SPIDAR-G can be seen at a website of ArachnoForce Inc. [37, 38] The visualization software was developed based on a chemical graphics library ChemoJun and a multimedia graphics library Jun . The basic requirements for a molecular haptic system were examined via experiments in the previous paper on HaptiChem . HaptiChem has two functions for feeling the intermolecular force for rare gas atoms (He, Ne, Ar, Kr, and Xe). One is the intermolecular force between two atoms (Figure ). A potential and force functions chart are drawn on the display, and the indicator pointing to the distance between the molecules simultaneously moves as user moves the molecule. User can thus better understand the relationships between the curve of functions and the changes of force. The other function is to feel the intermolecular force from multiple molecules (Figure ). The number of molecules and speed of motion can be changed. The user can feel the differences of states by changing them. We designed functions and graphic display as simple as possible for educational use, so that learner can easily grasp the meaning of the concept of molecular forces. The stability is also important to be used in schools. The processing speed became faster compared to the first version by improving the algorithm, so as to enhance stability of manipulation.