Bent molecular geometry

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Bent molecular geometry
Examples H2O, SO2
Point group C2v
Coordination number 2
Bond angle(s)90°<θ<120°
μ (Polarity) >0
Oxygen difluoride, an example of a molecule with the bent coordination geometry. Oxygen-difluoride-3D-vdW.png
Oxygen difluoride, an example of a molecule with the bent coordination geometry.

In chemistry, molecules with a non-collinear arrangement of two adjacent bonds have bent molecular geometry, also known as angular or V-shaped. Certain atoms, such as oxygen, will almost always set their two (or more) covalent bonds in non-collinear directions due to their electron configuration. Water (H2O) is an example of a bent molecule, as well as its analogues. The bond angle between the two hydrogen atoms is approximately 104.45°. [1] Nonlinear geometry is commonly observed for other triatomic molecules and ions containing only main group elements, prominent examples being nitrogen dioxide (NO2), sulfur dichloride (SCl2), and methylene (CH2).


This geometry is almost always consistent with VSEPR theory, which usually explains non-collinearity of atoms with a presence of lone pairs. There are several variants of bending, where the most common is AX2E2 where two covalent bonds and two lone pairs of the central atom (A) form a complete 8-electron shell. They have central angles from 104° to 109.5°, where the latter is consistent with a simplistic theory which predicts the tetrahedral symmetry of four sp3 hybridised orbitals. The most common actual angles are 105°, 107°, and 109°: they vary because of the different properties of the peripheral atoms (X).

Other cases also experience orbital hybridisation, but in different degrees. AX2E1 molecules, such as SnCl2, have only one lone pair and the central angle about 120° (the centre and two vertices of an equilateral triangle). They have three sp2 orbitals. There exist also sd-hybridised AX2 compounds of transition metals without lone pairs: they have the central angle about 90° and are also classified as bent.[ citation needed ] (See further discussion at VSEPR theory#Complexes with strong d-contribution).

See also

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In chemistry, a trigonal bipyramid formation is a molecular geometry with one atom at the center and 5 more atoms at the corners of a triangular bipyramid. This is one geometry for which the bond angles surrounding the central atom are not identical, because there is no geometrical arrangement with five terminal atoms in equivalent positions. Examples of this molecular geometry are phosphorus pentafluoride, and phosphorus pentachloride in the gas phase.

Octahedral molecular geometry Molecular geometry

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Atomic s character concentrates in orbitals directed toward electropositive substituents.

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In chemistry, the linear molecular geometry describes the geometry around a central atom bonded to two other atoms placed at a bond-angle of 180°. Linear organic molecules, such as acetylene (HC≡CH), are often described by invoking sp orbital hybridization for their carbon centers.

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Chemical bonding of water

Water is a simple triatomic bent molecule with C2v molecular symmetry and bond angle of 104.5° between the central oxygen atom and the hydrogen atoms. Despite being one of the simplest triatomic molecules, its chemical bonding scheme is nonetheless complex as many of its bonding properties such as bond angle, ionization energy, and electronic state energy cannot be explained by one unified bonding model. Instead, several traditional and advanced bonding models such as simple Lewis and VSEPR structure, valence bond theory, molecular orbital theory, isovalent hybridization, and Bent's rule are discussed below to provide a comprehensive bonding model for H
, explaining and rationalizing the various electronic and physical properties and features manifested by its peculiar bonding arrangements.


  1. Miessler, G. L.; Tarr, D. A. (2004). Inorganic Chemistry (3rd ed.). Pearson/Prentice Hall. ISBN   0-13-035471-6.