tetrahederal
linear
180°
trigonal planar
Anything with six electron groups, keep in mind an electron group is a bonded atom or an electron pair, is an octahedral. Anything in an octahedral and a lone pair is the square pyramidal geometry. So all angles between the atoms are a little less than 90 degrees and the angle of the electron pair is greater than 90.
The molecular geometry of a molecule can be determined using the VSEPR theory. VSEPR (Valence Shell Electron Pair Repulsion) Theory: The basic premise of this simple theory is that electron pairs (bonding and nonbonding) repel one another; so the electron pairs will adopt a geometry about an atom that minimizes these repulsions. Use the method below to determine the molecular geometry about an atom. Write the Lewis dot structure for the molecule. Count the number of things (atoms, groups of atoms, and lone pairs of electrons) that are directly attached to the central atom (the atom of interest) to determine the overall (electronic) geometry of the molecule. Now ignore the lone pairs of electrons to get the molecular geometry of the molecule. The molecular geometry describes the arrangement of the atoms only and not the lone pairs of electrons. If there are no lone pairs in the molecule, then the overall geometry and the molecular geometry are the same. If the overall geometry is tetrahedral, then there are three possibilities for the molecular geometry; if it is trigonal planar, there are two possibilities; and if it is linear, the molecular geometry must also be linear. The diagram below illustrates the relationship between overall (electronic) and molecular geometries. To view the geometry in greater detail, simply click on that geometry in the graphic below. Although there are many, many different geometries that molecules adopt, we are only concerned with the five shown below.
tetrahedral
Electron geometry for this is tetrahedral. There are two O-F single bonds, which makes 2 electron groups. There are two lone pairs around oxygen, which make up the last two electron groups. Molecules with four electron groups has a tetrahedral Electron geometry.
linear
three dimensional arrangement of atoms electron-group geometry
electron-group geometry
180°
109.5
trigonal planar
3 electron groups classified as trigonal planar. The molecular geometry is Angular or Bent whichever you prefer to call the shape. The ideal bond angles are 120 degrees and the molecule is polar.
trigonal pyramidal
Anything with six electron groups, keep in mind an electron group is a bonded atom or an electron pair, is an octahedral. Anything in an octahedral and a lone pair is the square pyramidal geometry. So all angles between the atoms are a little less than 90 degrees and the angle of the electron pair is greater than 90.
Shoshichi Kobayashi has written: 'Foundations of differential geometry' 'Transformation groups in differential geometry' -- subject(s): Differential Geometry, Geometry, Differential, Transformation groups