SiCl4 molecular geometry

SiCl4 molecular geometry has a tetrahedral shape with a bond angle of 109.5 ° between all Cl atoms and Si. Silicon tetrachloride is made from a combination of one of the most reactive and toxic elements (chlorine) and one of the most versatile elements on the planet (silicon). The Silicon tetrachloride corrodes cloth and metals. Used to produce high quality silica for commercial purposes. High-purity silicon tetrachloride used in the manufacture of optical fibers.

SiCl4 compound

The compound SiCl4 itself is extremely dangerous in nature and is used to extract pure silicon. It is used for a variety of purposes. This short article describes the molecular structure of SiCl4. Silicon tetrachloride is an inorganic compound that appears as a colorless, pungent, odorous liquid of the chemical formula SiCl4.

It can react violently with water to form white solid silicon dioxide and HCl gas. It dissolves in water. This article describes the Lewis structure of silicon tetrachloride (SiCl4), its molecular structure, hybrids, polar or non-polar, and more. Silicon tetrachloride corrodes cloth and metals. Used to produce high quality silica for commercial purposes. High-purity silicon tetrachloride used in the manufacture of optical fibers.

For a detailed article, the properties of silicon tetrachloride are listed below:

Characteristics of silicon tetrachloride

The characteristics of SiCl4 are as follows:

  • Soluble in benzene, toluene and water.

  • Looks like a colorless smoked liquid.

  • The boiling point is 57.65 ° C and the melting point is -68.74 ° C.

  • Has a tetrahedral crystal structure.

  • The coordination structure number of SiCl4 is 4.

This table is simply defined by the properties of silicon tetrachloride

Name of silicon tetrachloride Molecule
Chemical formula SiCl4
Molecular structure of SiCl4 tetrahedron
Electronic structure of SiCl4 tetrahedron
Hybridization Sp³
Bond angle 109.5 °
Total valence electron of SiCl4 32

To investigate the molecular structure of this compound, you need to be familiar with the “Lewis structural formula” of silicon tetrachloride (SiCl4).

Let’s see what the SiCL4 Lewis structure looks like here:

SiCl4 Lewis structure

Here you can see that silicon is located as the central atom and is surrounded by four chlorine atoms. With four valence electrons from Si and seven valence electrons from each Cl atom, silicon forms a single bond with all the chlorine atoms there, leaving three lone electron pairs for each chlorine atom and zero for silicon. Leaves a lone pair of electrons.

Next, we will explain the shape and bond angle of SiCl4. When a bond is formed, the outermost atoms (chlorine in this case) tend to repel each other and are as far apart as possible, due to the angle and shape of the connection.

Here, there is silicon in between and chlorine on the sides. In the 2D plane, the atoms seem to be arranged to form the shape below:

Molecule sicl4

However, the world is 3D like Avatar, where SiCl4 atoms are distributed in space and form a structure.

Sicl4 3d

This structure has a name. This is called Tetrahedron. The bond angle s / w of all Cl atoms and Si is 109.5 °. And not only SiCl4, but many other compounds form this form, with the central atom forming an angle of 109.5 ° with all outer atoms. Other compounds that give a tetrahedral shape are CH4, NH3, H2O, etc.


Silicon tetrachloride or tetrachlorosilane is an inorganic compound of the chemical formula SiCl4. A colorless volatile liquid that emits smoke in the air. It is used in the production of high-purity silicon and silicon dioxide for commercial use.

How do you draw the Lewis structure of SiCl4?

The structure of SiCl4 lewis is simple and very easy to draw. “The Lewis diagram shows the chemical bonds between the atoms in the molecule.” The Lewis structure of SiCl4 contains 12 lone pairs of electrons in the surrounding atom and zero in the central atom.

The Lewis structure of silicon tetrachloride has four pairs of bonds. Let’s see how to draw this step by step:

Follow a few steps to draw the Lewis point structure of SiCl4

1. Count the total valence electrons of SiCl4

First, determine the availability of SiCl4 valence electrons and find the valence electrons of silicon and chlorine atoms by the number of periodic groups. This is because silicon belongs to the 14th cycle group and chlorine belongs to the 17th cycle group.

Therefore, silicon has 4 valence electrons and chlorine has 7 valence electrons.

⇒ Total number of valence electrons in silicon = 4

⇒ Total number of valence electrons in chlorine = 7 Total number of valence electrons available in the Lewis structure of SiCl4 = 4 + 7 (4) = 32 valence electrons [ 1 silicon and 4 chlorine]

2. Find the smallest electronegative atom And place it in the following location.

center In the Lewis diagram, the atom with the lowest electronegativity tends to share more electrons than the atom with the strong electronegativity, so it always occupies the central position. The central atom is always connected to the surrounding atoms,

so it needs to share more electrons. Therefore, for SiCl4 made of silicon and chlorine, the electronegativity increases from left to right over a period of the periodic table, so silicon (1.8) has a lower electronegativity than chlorine (3.16).

Therefore, place the silicon in a central position and disperse all four chlorine atoms around it.

3. Connect the outer atom and the center atom with a single bond

In this step, all you have to do is connect all the outer atoms (chlorine) to the central atom (silicon) with a single bond. Next, count the valence electrons used in the above structure. As you can see, the above structure has four single bonds, which are used to connect all chlorine atoms (outside) to silicon atoms (center). Since a single bond contains two valence electrons,

the total of 32 available valence electrons (4 single bonds x 2) = 8 valence electrons are used to form the SiCl4 Lewis structure. I drew it (32-8) = 24-valence electron This leaves an additional 24 valence electrons.

4. First, place the remaining valence electrons, starting with the outer atom

In this step, the remaining valence electrons are first placed on the outer atom to complete their octet. Therefore, here chlorine is the outer atom, and each chlorine requires eight electrons to complete the octet. Therefore, the remaining valence electrons are placed on each chlorine atom until they fill the octet.

SiCl4 Lewis structure

As you can see in the structure above, we placed six valence electrons as dots around each chlorine atom. These chlorine atoms already share two electrons with the help of single bonds.

Therefore, every chlorine atom has eight electrons that it shares, which makes the octet convenient. Our central atom (silicon) also has four connected single bonds containing eight shared electrons, thus completing the octet. There are still 24 valence electrons, and in the above structure (6 valence electrons x 4 chlorine atoms) = 24 valence electrons were used.

  • (24-24) = 0 valence electrons remain

So we used all the available valence electrons (32) to draw the Lewis structure of silicon tetrachloride. All you need to do here is to calculate the formal charge of the SiCl4 molecule to confirm the stability of the above structure.

5. Use the formal loading concept to verify stability

Structures with zero or near zero formal charges are the best and most stable Lewis structures. Calculate the formal charge of an atom.
Use the following formula

⇒ Formal charge = (valence electron-lone pair of electrons-

1/2 shared electron pair)

To confirm the stability, calculate the formal charge of the 4th stage structure. For silicon atoms-

⇒Silicon valence electron = 4

⇒ Isolated electron pair on silicon = 0

⇒ Shared electron pair around silicon = 8

  • FC on silicon atom = (4-0-8 / 2) = 0

Chlorine atom-

⇒ Chlorine valence electron = 7

⇒Lone pair on chlorine = 6

⇒ Common electron pair around chlorine = 2

  • FC on chlorine atom = (7-6-2 / 2) = 0

  • SiCl4 All atoms of the Lewis structure (chlorine and silicon) receive a formal charge of zero.

Therefore, the above Lewis point structure of SiCl4 is the best and most stable because there is a formal charge at the zero point of every atom.


The central atom has no lone pair of electrons and has four bond pairs. Therefore, since SiCl4 is an EX4 type molecule, it has a tetrahedral shape. SiCl4 is non-polar because the attractive forces between the shared electron pairs are the same and the molecules are symmetric.

What is the molecular structure of SiCl4?

The molecular structure of SiCl4 is a tetrahedron, and a repulsive force is generated by the electron pair around the central atom, so that all four external atoms (chlorine) are pushed out from the central atom (silicon) in all directions.

“A tetrahedron means having four faces.” The four SiCl bonds in the SiCl4 geometry replace the corners of a regular tetrahedron, so their shape actually looks like a tetrahedron. According to VSEPR theory, when the central atom (silicon) is bonded to four bonded atoms (chlorine), the electron pairs around the central atom repel each other and all the angular atoms (chlorine) spread as much as possible.

Takes a place with minimal repulsion and much better stability.

As can be seen from the structure on , electron pair repulsion (BP + BP and LP + BP) occurs, and surrounding atoms push the atoms as much as possible (adjacent and opposite) to maximize the distance and repulsion between them. The force is minimal. Therefore, all of these distributed atoms replace the usual tetrahedral corners.

Therefore, it can be said that the molecular structure of SiCl4 is tetrahedral. If the molecular structure of SiCl4 cannot be visualized, theoretically the AXN method and VSEPR diagram can be used to determine its shape.

Therefore, the AXN notation follows, as shown in the figure above.

Next, you need to find the molecular structure of SiCl4 using this method.

SiCl4 molecule AXN notation:

The AXN notation for SiCl4 molecules is shown below.

  • A represents the central atom. Therefore, according to the SiCl4 Lewis structure, silicon is the central atom. A = Silicon

  • X represents a bond atom. As you know, silicon forms four bonds with the chlorine atom. Therefore, X = 4

  • N represents the lone pair of electrons in the central atom, and the lone pair of electrons in the silicon atom is zero. Therefore, N = 0

Therefore, the AXN notation for SiCl4 molecules is AX4N0 or AX4. According to the VSEPR diagram, if the central atom of a molecule contains 0 lone pairs of electrons and is pushed into a corner by the four surrounding atoms, the molecular shape of this molecule will be a tetrahedron. Therefore, the molecular shape or shape of SiCl4 is tetrahedral.

SiCl4 molecular structure

The electronic structure of SiCl4 is also a tetrahedron.

SiCl4 hybridization

According to the hybrid orbital, “two or more orbitals overlap to form two or more hybrid orbitals of the same energy and shape.” To determine the hybrid of molecules, it is first necessary to determine the number of hybrids or steric numbers of the central atom. Note: The number of steric numbers and the number of hybridizations are the same.

"The steric number is the number of atoms bonded to the central atom of the molecule plus the number of lone pairs of electrons bonded to the central atom."

  • steric number of SiCl4 = (number of bonded atoms bonded to silicon + lonely pair on silicon)

According to the Lewis structure of SiCl4, the silicon atom in the center is bonded to four chlorine atoms, and there is one zero pair on it.

  • steric number of SiCl4 = (4 + 0) = 4
Steric number Hybridization
1 S
2 Sp
3 Sp²
4 Sp³
5 Sp³d
6 Sp³d²

So, for a steric number of four, we get the Sp3 hybridization on the SiCl4 molecule.

The bond angle of SiCl4

“A bond angle is the angle between two atoms in a molecule”.

The bond angle of SiCl4 is 109.5° as the shape of its tetrahedral in nature and as per the VSEPR theory, a regular tetrahedral molecule holds that bond angle of 109.5º.

So, the bond angle of Cl – Si – Cl = 109.5°.

Silicon tetrachloride extremity: is SiCl4 polar or nonpolar?

A polar molecule is awry contains solitary pair and has some dipole second while non-polar molecules are exceptionally balanced contain no unshared electrons and have net dipole second zero.

Anyway, Is SiCl4 polar or nonpolar? SiCl4 is a nonpolar molecule in nature as its shape is exceptionally balanced, additionally its focal iota doesn’t contain any solitary pair, henceforth contortion of shape doesn’t occur.

Assuming you see the moleculargeometry of SiCl4, each of the four chlorine molecules are similarly separated around the silicon iota in a tetrahedron corner. Consequently, the dipole second produced along the bond can be effortlessly counterbalanced, leaving this molecule nonpolar in nature with net dipole second zero.

Dipole second produced alongside the bond(Si-Cl) because of the division of charge initiated on particles, this charge is instigated in light of the fact that the electronegativity of chlorine is 3.16 and for silicon, it is 1.90. The distinction of the electronegativity between these molecules high, this makes a Si-Cl polar covalent bond in nature.

Albeit the bonds inside a molecule(SiCl4) are polar in nature however the construction of SiCl4 is exceptionally even, this causes a uniform charge dissemination in the entire molecule.

Thus, dropping dipole in SiCl4 turns into a great deal simple leaving this molecule nonpolar in nature.


The CCl4 and SiCl4 are tetrahedral on the grounds that both structure the bond point of 109.5° between the four chlorines. The Brainliest Answer! Clarification: Because,the VSEPR units of the two iotas are 4 and it implies the electrogeometry is tetrahedral.As there are no solitary sets in the two particles, the shape stays at tetrahedral.

Frequently Asked Questions FAQ

The most frequently asked questions about SiCl4 molecular geometry are given below to enhance your knowledge:

1. For what reason is the molecular geometry of SiCl4 is same as its electron geometry?

The molecular geometry of SiCl4 is tetrahedral and its electron geometry is likewise tetrahedral in light of the fact that according to VSEPR hypothesis, molecular shape considers just bond sets or particles while electron geometry considers reinforced molecules just as solitary sets present on the focal iota.

As per the lewis design of SiCl4, the focal atom(silicon) doesn’t contain any solitary pair on it.

Subsequently, just reinforced particles are utilized to decide the geometry of SiCl4.

Consequently, Molecular geometry of SiCl4 = Electron geometry of SiCl4 [ no solitary pair on focal iota of SiCl4]

2. What number of solitary pair and reinforced pair electrons a lewis construction of SiCl4 contains?

The focal atom(silicon) is appended to the chlorine molecules with four single bonds(bonded pair).

One fortified pair contains two electrons, consequently, (4 × 2) = 8 reinforced pair electrons present in the lewis construction of Silicon tetrachloride.

Likewise, solitary pair electrons are additionally called unshared electrons, silicon iotas have no solitary pair while every chlorine molecule contains 3 solitary sets on it.

Thus, (4 chlorine iotas × 3 solitary sets on each) = 12 solitary sets.

  • (12 × 2) = 24 solitary pair electrons are available in the lewis design of SiCl4.

3. What is the atomic geometry and molecular extremity for SiCl4?

SiCl4 is nonpolar in nature, in spite of the fact that, its bonds are polar. The general proper charge in Silicon tetrachloride is zero. Complete 24 solitary sets electrons and 8 fortified sets electrons present in SiCl4 lewis dab structure. The molecular geometry of SiCl4 is tetrahedral and electron geometry is additionally tetrahedral.

4. Is SiCl4 three-sided planar?

This is an AX4 - type molecule, with four Si-Cl bonds. As indicated by VSEPR hypothesis, these bonds should point towards the sides of a customary tetrahedron. So SiCl4 has a tetrahedral shape.

5. What is the atomic geometry of SiH4?

Silicon Tetrahydride , SiH4 Molecular Geometry and Polarity. Then, at that point, draw the 3D molecular design utilizing VSEPR rules: Decision: The molecular geometry of SiH4 is tetrahedral with symmetric charge appropriation around the focal iota.

6. What is the bond point of SiCl4?


The bond points in SiCl4 are 109°. The VSEPR (valence shell electron pair aversion) state of a molecule is its molecular geometry that is based.

7. What is the electron pair geometry for BrF5?

As per the VSEPR hypothesis, the molecular geometry of BrF5 is square pyramidal and its electron geometry is octahedral on the grounds that bromine being the focal molecule has five bonds associated with encompassing fluorine iotas.

8. What is the geometry of OF2?

The electron geometry of OF2 is tetrahedral and molecular geometry is Bent.

9. Is SiCl4 ionic or sub-atomic?

Silicon is metalloid and it is likewise considered as nonmetallic and chlorine is additionally a nonmetal and the connection among metals and non metal is ionic just as connection among nonmetals and nonmetals are covalent. So SiCl4 is covalent.

10. For what reason does SiCl4 respond with water?

In SiCl4, focal iota Si has empty 3d orbital which can oblige the electron pair from the oxygen particle of H2O molecules and accordingly they become ready to perform hydrolysis to deliver the final result Silicic corrosive [Si(OH)4] by SN2 instrument.

11. Is SiCl4 a molecular strong?

Clarification: SrCl2 is an ionic compound. In strong SrCl2 theparticles are organized in a cross section structure, held together by solid ionic connections between the oppositely charged Sr2+ and Cl− particles. SiCl4 is a covalent compound, thus in strong SiCl4 , the molecules are held together by frail intermolecular powers.


The absolute valence electron is accessible for the Silicon tetrachloride (SiCl4) lewis structure is 32.The hybridization of the SiCl4 molecule is Sp3. The bond point of SiCl4 is 109.5º. SiCl4 is nonpolar in nature, despite the fact that, its bonds are polar. The general conventional charge in Silicon tetrachloride is zero. Absolute 24 solitary sets electrons and 8 reinforced sets electrons present in SiCl4 lewis spot structure. The molecular geometry of SiCl4 is tetrahedral and electron geometry is additionally tetrahedral.

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