Molecular Geometry & Lewis Structures
Electron-domain analysis, geometry, bond angle and step-by-step construction for NF3 (CAS 7783-54-2) — with the practical supply context B2B and laboratory buyers need.
NF3 has a Trigonal pyramidal molecular geometry (AX3E, tetrahedral) with a bond angle of ≈102° (against 107.8° in NH3). The central nitrogen carries 3 bonding domain(s) and 1 lone pair(s) — 4 electron domains in total. Electronegative fluorine pulls bonding electrons away from nitrogen, shrinking bonding-pair repulsion; the lone pair then dominates and squeezes the angle further than in ammonia.
Hybridisation is conventionally described as sp3. Polarity: Slightly polar; the small net dipole points opposite the lone pair, cancelling much of NH3-style basicity.
| Parameter | Nitrogen Trifluoride (NF3) |
|---|---|
| CAS Registry Number | 7783-54-2 |
| Molecular formula | NF3 |
| Molar mass | 71.002 g/mol |
| Total valence electrons | 26 |
| Central atom | Nitrogen |
| Bonding domains (σ) | 3 |
| Lone pairs on central atom | 1 |
| Electron domains (steric number) | 4 |
| Electron-pair geometry | Tetrahedral |
| Molecular geometry (shape) | Trigonal pyramidal |
| VSEPR notation | AX3E |
| Bond angle | ≈102° (against 107.8° in NH3) |
| Hybridisation (conventional) | sp3 |
| Polarity | Slightly polar; the small net dipole points opposite the lone pair, cancelling much of NH3-style basicity. |
| Lewis structure guide | NF3 Lewis structure |
Molar mass is the average value rounded for procurement use. Hybridisation labels are the conventional VSEPR-level description; orbital treatment becomes more nuanced at higher levels of theory.
A worked diagram of this molecule is kept in the companion guide: NF3 Lewis structure.
VSEPR theory counts electron domains — every σ bond counts once regardless of bond order, and every lone pair counts once. NF3 has 4 such domains around the nitrogen: 3 bonding and 1 lone. 4 domains correspond to a tetrahedral electron-domain arrangement; with 1 lone pair excluded from the shape the observed molecular shape is trigonal pyramidal (AX3E).
Bond angle: ≈102° (against 107.8° in NH3) because electronegative fluorine pulls bonding electrons away from nitrogen, shrinking bonding-pair repulsion; the lone pair then dominates and squeezes the angle further than in ammonia.
Polarity: Slightly polar; the small net dipole points opposite the lone pair, cancelling much of NH3-style basicity.
Geometry shortcut for recall
Steric number 4 → parent arrangement tetrahedral; subtract 1 lone position and the visible shape is trigonal pyramidal. Same electron count, different lone-pair bookkeeping, different geometry — always count the domains before naming the shape.
Assuming the ammonia angle — identical VSEPR types still shift when the ligands change electronegativity.
Nitrogen carries eight electrons.
Plasma etch and chamber-clean gas in semiconductor fabs; environmental handling clauses reflect its very high global warming potential.
Structure-level identity is exactly what a purchase order has to fix: the same molecular formula can hide isomers, hydrates or salt forms with different handling profiles. Before ordering, match CAS (7783-54-2), assay, water content and container rating against the datasheet, and request the COA batch that will ship.
Trigonal pyramidal. The 4 electron domains around the central nitrogen adopt a tetrahedral arrangement, and with 1 lone pair in place the visible shape is trigonal pyramidal.
≈102° (against 107.8° in NH3), because electronegative fluorine pulls bonding electrons away from nitrogen, shrinking bonding-pair repulsion; the lone pair then dominates and squeezes the angle further than in ammonia.
Slightly polar; the small net dipole points opposite the lone pair, cancelling much of NH3-style basicity.
NF3 carries 1 lone pair on the central nitrogen.
Editorial note
This page explains molecular geometry and Lewis-structure construction for education and procurement due-diligence. It is not a safety datasheet; for handling, exposure and transport limits consult the current SDS and local regulations.