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molecular shape
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Diagram showing VSEPR electron pair arrangements and their corresponding molecular shapes, including linear, trigonal planar, angular, tetrahedral, trigonal pyramidal, trigonal bipyramidal, seesaw, T-shaped, octahedral, square pyramidal, and square planar geometries. Each arrangement is illustrated with red lines and electron pairs.
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molecular shape

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Diagram showing VSEPR electron pair arrangements and their corresponding molecular shapes, including linear, trigonal planar, angular, tetrahedral, trigonal pyramidal, trigonal bipyramidal, seesaw, T-shaped, octahedral, square pyramidal, and square planar geometries. Each arrangement is illustrated with red lines and electron pairs.
electron pairs and molecular shape VSEPR electron pair arrangements and associated molecular shapes.

Molecular shape refers to the three-dimensional arrangement of atoms within a molecule. This arrangement is determined by the directional nature of covalent bonds, unlike the nondirectional ionic bonds. The Valence-Shell Electron-Pair Repulsion (VSEPR) theory is a model used to predict these shapes. It posits that electron pairs (both bonding and lone pairs) around a central atom repel each other, and the molecular shape adjusts to minimize these repulsions.12

For example, methane (CH4) has a tetrahedral shape because its four electron pairs arrange themselves to be as far apart as possible. Water (H2O) has an angular shape due to two bonding pairs and two lone pairs around the oxygen atom. While some molecules form rings, like cyclopropane, others, such as boron trifluoride (BF3), exhibit trigonal planar geometry. The specific shape of a molecule is crucial, as it significantly influences its properties.1234

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6 Britannica Sources
  1. chemical bonding - Limitations of the VSEPR model
  2. Are There Triangular Molecules?
  3. chemical bonding - Applying VSEPR theory to simple molecules
  4. chemical bonding - Molecular structure
  5. chemical bonding - Molecules with no central atom
  6. cluster - Comparison with molecules

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