Creating Chemistry-related Mobile Apps

Dr Emelyn Tan / Dr Soo Yuen Jien

As part of the LIFT grant, we (Chemistry and SoC) created and implemented 5 mobile apps, available for free on Apple App Store and Google Play Store. Each of the apps were created to solve their own problem, however, for the purpose of this video, will focus on the more visually appealing one – “3D SYM OP” which helps with spatial visualisation.

What Used to Be

The bands in Infrared (IR) spectra are due to vibrations of the molecule. Vibrations of the molecule is dependent on its symmetry or lack of. Hence, in the interpretation of bands in IR spectra, molecular symmetry present has to be established.

Traditionally, a 3D drawing on the 2D whiteboard is drawn and students do mental manipulations (symmetry operations) to work out its symmetry elements, for example, the molecule below can be rotated by 360° / 4 = 90° around a vertical axis and so has a C4 rotation axis.

Problems We Identified

Certain students have difficulty doing the mental manipulations, leading to difficulty in identifying the symmetry elements, followed by inability to then assign vibrations to bands in the IR spectrum.

What We Did

We created the mobile app “3D SYM OP” that students use in App Assisted Interactive Tutorials (AAIT).

“3D Sym Op” is an educational app designed to visualise the symmetry elements and operations on molecules of various point groups. The 3D molecule is searchable via four ways: Name, Formula; 2D Structure; Point Group and Image Recognition. Symmetry elements – rotation axis (C); reflection plane; inversion point (i) and improper rotation (S) can be selectively displayed on the scalable 3D molecule. On touch the symmetry operation e.g. C6 – 60o rotation, is performed and user can pause/resume movement at any time. The corresponding 2D image with symmetry element can also be shown. Tapping the point group would display the character table. A quiz mode is available for which each time has 7 symmetry element questions followed by 3 point group questions, for self-assessment.

In one of the AAITs, rather than doing the mental manipulation, the app allows the molecule to be operated on, i.e. rotate, reflect, invert, according to the symmetry element, aiding dynamic spatial visualisation. Following that, the students draw out the molecule together with its symmetry elements, reinforcing the dynamic spatial visualisation.

How This Helped

The post-test vs. pre-test % increase for those who used the app more frequently (Very Frequently, Frequently and Occasionally) is greater compared to those who use the app rarely (Rarely, Very Rarely, Do not use / Do not have). To the statement of “3D Sym Op” app is overall effective, a score of 4.4 out of 5 was obtained, with the majority of 57 students agreeing with the statement.