A. F. Kapauan
Ateneo d e Manila University Quezon City, Philippines
Cardboard Orbital Domain Models
A n article in Tms JOURNAL,^ by A. I/Y. Adamson prescnted a novel way of visualizing atomic orbitals. The space around the nucleus is divided into "domains," each domain representing the orbital whose electron density predominates in that region. He also described a method for making the various orbital domain models out of plastic. However, this procedure seems unduly difficult and expensive. The cardboard models presented in the same article do not show the domains as clearly as the plastic models do. Cardboard models which possess most of t,he properties of the plastic models can be made quite easily and inexpensively. Pyramidal sectors of a sphere are made from suitably cut, creased, and folded pieces of cardboard which are then cemented together to form the solid models (Fig. 1). Patterns for the spa,p, d and f orbital domain models are presented in Figure 2. As shown in the figure, the spa and p models require only one kind of sector while the d and f models require two and three different kinds, respectively.
ADAMSON,A. W., 3. CHEM.EDUC., 42, 140 (1965)
I n assembling the d orbital domaiu model, the square sectors go along the six directions of the Cartesian axes, while the hexagonal sectors go into the 45" dirertions between them. Octagonal sectors in the j' orbital model lie along the six Cartesian directions, while the rectangular sectors go into the 45" directions hrtmeen
Figure 1. models.
Stager in the construction of cordboord p and d orbital domain
make 4
make 6
s ~3
P RADIUS
make 6
make 12
d = 100.0
C = 46.
make 1 2
C = 61.6
make 6
make 8
f Figure 2.
Panernr for the cardboard sectors of the rpJ, p, d, and f models.
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them. The hexagonal sectors will then fit into the spaces between the octagonal and rectangular sectors. Colorcd cardboard is used. The p orbital model requires three colors, the sp3 four colors, the d four color.
