Ti 22

Titanium (Ti)

transition-metal

Period: 4 Group: 4 Block: s

Solid

Standard Atomic Weight

Electron configuration

[Ar] 4s² 3d²

Melting point

1667.85 °C (1941 K)

Boiling point

3286.85 °C (3560 K)

Density

4500 kg/m³

Oxidation states

−2, −1, 0, +1, +2, +3, +4

Electronegativity (Pauling)

1.54

Ionization energy (1st)

Discovery year

1791

Atomic radius

140 pm

Details

Name origin Greek: titanos (Titans).

Discovery country England

Discoverers William Gregor

Titanium is a light, strong transition metal with a high melting point and exceptional resistance to corrosion in many natural and industrial environments. Its chemistry is dominated by the +4 oxidation state, although +3 and lower states occur in specialized compounds. The metal is abundant in Earth’s crust but is rarely found in concentrated metallic form because it bonds strongly to oxygen and nitrogen. Its combination of low density, strength, and passivation makes it important in aerospace, chemical equipment, pigments, and medical materials.

Titanium, when pure, is a lustrous, white metal. It has a low density, good strength, is easily fabricated, and has excellent corrosion resistance. It is ductile only when it is free of oxygen. The metal, which burns in air, is the only element that burns in nitrogen.

Titanium is resistant to dilute sulfuric and hydrochloric acid, most organic acids, most chlorine gas, and chloride solutions.

Natural titanium is reported to become very radioactive after bombardment with deuterons. The emitted radiations are mostly positrons and hard gamma rays. The metal is dimorphic. The hexagonal alpha form changes to the cubic beta form very slowly at about 880°C. The metal combines with oxygen at red heat, and with chlorine at 550°C.

Titanium metal is considered to be physiologically inert. When pure, titanium dioxide is relatively clear and has an extremely high index of refraction with an optical dispersion higher than diamond.

The name derives from the Latin titans, who were the mythological "first sons of the earth". It was originally discovered by the English clergyman William Gregor in the mineral ilmenite (FeTiO3) in 1791. He called this mineral menachanite and the element menachin, for the Menachan parish where it was found. It was rediscovered in 1795 by the German chemist Martin Heinrich Klaproth, who called it titanium because it had no characteristic properties to use as a name. Titanium metal was first isolated by the Swedish chemists Sven Otto Pettersson and Lars Fredrik Nilson.

Titanium was discovered in 1791 by the Reverend William Gregor, an English pastor. Pure titanium was first produced by Matthew A. Hunter, an American metallurgist, in 1910. Titanium is the ninth most abundant element in the earth's crust and is primarily found in the minerals rutile (TiO2), ilmenite (FeTiO3) and sphene (CaTiSiO5). Titanium makes up about 0.57% of the earth's crust.

From the Latin titans, the first sons of the Earth, Greek mythology.

Discovered by Gregor in 1791; named by Klaproth in 1795. Impure titanium was prepared by Nilson and Pettersson in 1887; however, the pure metal (99.9%) was not made until 1910 when Hunter heated TiCl4 with sodium in a steel bomb.

Read about Titanium on Wikipedia

Images

Properties

Physical

Atomic radius (empirical) 140 pm

Covalent radius 160 pm

Van der Waals radius 187 pm

Metallic radius 132 pm

Density

Molar volume 0.0106 L/mol

Phase at STP solid

Melting point 1667.85 °C

Boiling point 3286.85 °C

Thermal conductivity 21.9 W/(m·K)

Specific heat capacity 0.523 J/(g·K)

Molar heat capacity 25.06 J/(mol·K)

Crystal structure hcp

Chemical

Electronegativity (Pauling) 1.54

Electronegativity (Allen) 1.38

Electron affinity

Ionization energy (1st)

Ionization energy (2nd)

Ionization energy (3rd)

Ionization energy (4th)

Ionization energy (5th)

Oxidation states −2, −1, 0, +1, +2, +3, +4

Valence electrons 4

Electron configuration

Electron configuration (semantic)

Thermodynamic

Heat of fusion 0.14665492 eV

Heat of vaporization 4.40483 eV

Heat of sublimation 4.851531 eV

Heat of atomization 4.851531 eV

Atomization enthalpy

Nuclear

Stable isotopes 5

Discovery year 1791

Abundance

Abundance (Earth's crust) 5650 mg/kg

Abundance (ocean)

Reactivity

N/A

Crystal Structure

Lattice constant a 295 pm

Electronic Structure

Electrons per shell 2, 8, 10, 2

Identifiers

CAS number 7440-32-6

Term symbol

InChI InChI=1S/Ti

InChI Key RTAQQCXQSZGOHL-UHFFFAOYSA-N

Electron Configuration Measured

Ion charge

Protons 22

Electrons 22

Charge Neutral

Configuration Ti: 3d² 4s²

[Ar] 3d² 4s²

1s² 2s² 2p⁶ 3s² 3p⁶ 3d² 4s²

Orbital diagram

↑↓

2/2

↑↓

2/2

↑↓

6/6

↑↓

2/2

↑↓

6/6

↑↓

2/2

↑

2/10 2↑

Total electrons: 22 Unpaired: 2

Atomic model

Protons 22

Neutrons 26

Electrons 22

Mass number 48

Stability Stable

Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.

Schematic atomic model, not to scale.

Atomic Fingerprint

Emission / Absorption Spectrum

Emission Visible: 380–750 nm

Isotope Distribution

Mass number	Atomic mass (u)	Natural abundance	Half-life
46 Stable	45.95262772 ± 0.00000035	8.2500%	Stable
47 Stable	46.95175879 ± 0.00000038	7.4400%	Stable
48 Stable	47.94794198 ± 0.00000038	73.7200%	Stable
49 Stable	48.94786568 ± 0.00000039	5.4100%	Stable
50 Stable	49.94478689 ± 0.00000039	5.1800%	Stable

Measured

Phase / State

Solid 25 °C (298.15 K)

Reason: 1642.8 °C below melting point (1667.85 °C)

Melting point 1667.85 °C

Boiling point 3286.85 °C

Below melting by 1642.8 °C

0 K Current temperature: 25 °C 6000 K

Phase timeline

Schematic, not to scale

Solid

Liquid

Gas

Melting

Boiling

25°C

Solid

Liquid

Gas

Current

Phase transition points

Melting point Literature

1667.85 °C

Boiling point Literature

3286.85 °C

Current phase Calculated
Solid

Transition energies

Heat of fusion Literature

0.14665492 eV

Energy required to melt 1 mol at melting point

Heat of vaporization Literature

4.40483 eV

Energy required to vaporize 1 mol at boiling point

Heat of sublimation Literature

4.851531 eV

Energy required to sublime 1 mol at sublimation point

Density

Reference density Literature

4500 kg/m³

At standard conditions

Current density Calculated

4500 kg/m³

At standard conditions

Atomic Spectra

Showing 10 of 22 Atomic Spectra. Sorted by ion charge (ascending).

Lines Holdings ?

Ion	Charge	Total lines	Transition probabilities	Level designations
Ti I	0	4029	496	4029
Ti II	+1	1872	470	1872
Ti III	+2	819	297	819
Ti IV	+3	86	39	86
Ti V	+4	252	4	252
Ti VI	+5	71	14	71
Ti VII	+6	92	13	92
Ti VIII	+7	85	37	85
Ti IX	+8	85	50	85
Ti X	+9	162	78	162

NIST Lines Holdings →

Levels Holdings ?

Ion	Charge	Levels
Ti I	0	559
Ti II	+1	253
Ti III	+2	200
Ti IV	+3	40
Ti V	+4	66
Ti VI	+5	59
Ti VII	+6	62
Ti VIII	+7	44
Ti IX	+8	32
Ti X	+9	83

NIST Levels Holdings →

22 Ti 47.867

Titanium — Atomic Orbital Visualizer

[Ar]4s23d2

Energy levels 2 8 10 2

Oxidation states -2, -1, 0, +1, +2, +3, +4

HOMO 3d n=3 · l=2 · m=-2

Titanium — Atomic Orbital Visualizer Preview

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22 Ti 47.867

Titanium — Crystal Structure Visualizer

Primitive Hexagonal · Pearson hP2

Experimental

Pearson hP2

Coord. № 12

Packing 74.048%

Titanium — Crystal Structure Visualizer Preview

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Ionic Radii

Charge	Coordination	Spin	Radius
+2	6	N/A	86 pm
+3	6	N/A	67 pm
+4	4	N/A	42 pm
+4	5	N/A	51 pm
+4	6	N/A	60.5 pm
+4	8	N/A	74 pm

Compounds

47.867 u

Ti+4

47.867 u

44.958 u

43.960 u

Ti+2

47.867 u

Ti+3

47.867 u

46.952 u

50.947 u

51.947 u

45.953 u

47.948 u

48.948 u

49.945 u

Isotopes (5)

Natural titanium consists of five isotopes with atomic masses from 46 to 50. All are stable. Eight other unstable isotopes are known.

Mass number	Atomic mass (u)	Natural abundance	Half-life	Decay mode
46 Stable	45.95262772 ± 0.00000035	8.2500% ± 0.0300%	Stable	stable
47 Stable	46.95175879 ± 0.00000038	7.4400% ± 0.0200%	Stable	stable
48 Stable	47.94794198 ± 0.00000038	73.7200% ± 0.0300%	Stable	stable
49 Stable	48.94786568 ± 0.00000039	5.4100% ± 0.0200%	Stable	stable
50 Stable	49.94478689 ± 0.00000039	5.1800% ± 0.0200%	Stable	stable

46 Stable

Atomic mass (u) 45.95262772 ± 0.00000035

Natural abundance 8.2500% ± 0.0300%

Half-life Stable

Decay mode

stable

47 Stable

Atomic mass (u) 46.95175879 ± 0.00000038

Natural abundance 7.4400% ± 0.0200%

Half-life Stable

Decay mode

stable

48 Stable

Atomic mass (u) 47.94794198 ± 0.00000038

Natural abundance 73.7200% ± 0.0300%

Half-life Stable

Decay mode

stable

49 Stable

Atomic mass (u) 48.94786568 ± 0.00000039

Natural abundance 5.4100% ± 0.0200%

Half-life Stable

Decay mode

stable

50 Stable

Atomic mass (u) 49.94478689 ± 0.00000039

Natural abundance 5.1800% ± 0.0200%

Half-life Stable

Decay mode

stable

Spectral Lines

Showing 50 of 1717 Spectral Lines. Only spectral lines with measured intensity are shown by default.

Wavelength (nm)	Intensity	Ion stage	Type	Transition	Accuracy	Source
521.03843 nm	21000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3F	Measured	NIST
506.46526 nm	17000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3D	Measured	NIST
519.29686 nm	17000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3F	Measured	NIST
517.37431 nm	15000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3F	Measured	NIST
498.17305 nm	14000	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
503.99574 nm	14000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3D	Measured	NIST
468.19089 nm	13000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3G	Measured	NIST
499.1066 nm	13000	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
499.9503 nm	12000	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
501.41861 nm	11000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3D	Measured	NIST
399.86363 nm	10000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(1P) y 3F	Measured	NIST
466.75845 nm	10000	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3G	Measured	NIST
500.72093 nm	10000	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
453.32394 nm	9200	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
398.17616 nm	8800	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(1P) y 3F	Measured	NIST
398.97582 nm	8800	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(1P) y 3F	Measured	NIST
501.42762 nm	8700	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
395.82055 nm	8600	Ti I	emission	3d2.4s2 a 3F → 3d3.(4F).4p y 3D*	Measured	NIST
465.64693 nm	8400	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(3P) z 3G	Measured	NIST
395.63338 nm	8000	Ti I	emission	3d2.4s2 a 3F → 3d3.(4F).4p y 3D*	Measured	NIST
453.47761 nm	7900	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
394.86705 nm	7000	Ti I	emission	3d2.4s2 a 3F → 3d3.(4F).4p y 3D*	Measured	NIST
484.08737 nm	6600	Ti I	emission	3d2.4s2 a 1D → 3d2.(1D).4s.4p.(1P) y 1D	Measured	NIST
430.59074 nm	6400	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p x 5D*	Measured	NIST
453.55686 nm	6100	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
394.77683 nm	5700	Ti I	emission	3d2.4s2 a 3F → 3d2.(1D).4s.4p.(3P) 3P	Measured	NIST
502.00263 nm	5100	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
430.10787 nm	4900	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p x 5D*	Measured	NIST
503.5903 nm	4900	Ti I	emission	3d3.(4F).4s b 3F → 3d3.(4F).4p w 3G*	Measured	NIST
502.28679 nm	4800	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
453.59176 nm	4700	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
430.05538 nm	4400	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p x 5D*	Measured	NIST
453.60403 nm	4000	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
503.64639 nm	4000	Ti I	emission	3d3.(4F).4s b 3F → 3d3.(4F).4p w 3G*	Measured	NIST
501.61609 nm	3800	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
451.8022 nm	3700	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
488.50794 nm	3700	Ti I	emission	3d3.(2G).4s a 3G → 3d3.(2G).4p y 3H*	Measured	NIST
392.45264 nm	3600	Ti I	emission	3d2.4s2 a 3F → 3d3.(4F).4p y 3D*	Measured	NIST
402.45711 nm	3600	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(1P) y 3F	Measured	NIST
390.47826 nm	3500	Ti I	emission	3d2.4s2 a 1D → 3d2.(1D).4s.4p.(1P) y 1F	Measured	NIST
452.2797 nm	3500	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
502.48444 nm	3500	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5G*	Measured	NIST
398.24811 nm	3400	Ti I	emission	3d2.4s2 a 3F → 3d2.(3P).4s.4p.(3P) z 5S	Measured	NIST
454.87635 nm	3400	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
455.24533 nm	3400	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p y 5F*	Measured	NIST
400.89274 nm	3300	Ti I	emission	3d2.4s2 a 3F → 3d2.(3F).4s.4p.(1P) y 3F	Measured	NIST
503.83979 nm	3300	Ti I	emission	3d3.(4F).4s b 3F → 3d3.(4F).4p w 3G*	Measured	NIST
392.98737 nm	3200	Ti I	emission	3d2.4s2 a 3F → 3d3.(4F).4p y 3D*	Measured	NIST
429.86657 nm	3200	Ti I	emission	3d3.(4F).4s a 5F → 3d3.(4F).4p x 5D*	Measured	NIST
489.99088 nm	3200	Ti I	emission	3d3.(2G).4s a 3G → 3d3.(2G).4p y 3H*	Measured	NIST

Extended Properties

Covalent Radii (Extended)

Covalent radius (Pyykkö)

Covalent radius (Pyykkö, double)

Covalent radius (Pyykkö, triple)

Covalent radius (Bragg)

Van der Waals Radii

Batsanov

Alvarez

UFF

MM3

Atomic & Metallic Radii

Atomic radius (Rahm)

Metallic radius (C12)

Numbering Scales

Mendeleev

Pettifor

Glawe

Electronegativity Scales

Ghosh

Miedema

Gunnarsson–Lundqvist

Robles–Bartolotti

Polarizability & Dispersion

Dipole polarizability

Dipole polarizability (unc.)

C₆

C₆ (Gould–Bučko)

Chemical Affinity

Proton affinity

Gas basicity

Miedema Parameters

Miedema molar volume

Miedema electron density

Supply Risk & Economics

Production concentration

Relative supply risk

Reserve distribution

Political stability (top producer)

Political stability (top reserve)

Phase Transitions & Allotropes

Melting point	1943.15 K
Boiling point	3560.15 K

Oxidation State Categories

−1 extended

+2 extended

−2 extended

+3 extended

0 extended

+1 extended

+4 main

Advanced Reference Data

Screening Constants (7)

n	Orbital	σ
1	s	0.5591
2	p	3.9352
2	s	6.6234
3	d	13.8586
3	p	11.8963
3	s	10.9669
4	s	17.1832

Crystal Radii Detail (6)

Charge	CN	r_crystal (pm)	Origin
2	VI	100	estimated,
3	VI	81	from r^3 vs V plots,
4	IV	56	calculated,
4	V	65	calculated,
4	VI	74.5	from r^3 vs V plots,
4	VIII	88	calculated,

Isotope Decay Modes (47)

Isotope	Mode	Intensity
37	p	—
38	2p	—
39	B+	100%
39	B+p	93.7%
39	2p	—
40	B+	100%
40	B+p	95.8%
41	B+	100%
41	B+p	91.1%
42	B+	100%

X‑ray Scattering Factors (530)

Energy (eV)	f₁	f₂
10	—	1.51668
10.1428	—	1.54246
10.3068	—	1.57217
10.4735	—	1.60245
10.6429	—	1.63331
10.8151	—	1.66477
10.99	—	1.70636
11.1677	—	1.75257
11.3484	—	1.80003
11.5319	—	1.84878

Additional Data

Estimated Crustal Abundance

The estimated element abundance in the earth's crust.

5.65×103 milligrams per kilogram

References (1)

[5] Titanium https://education.jlab.org/itselemental/ele022.html

Estimated Oceanic Abundance

The estimated element abundance in the earth's oceans.

1×10-3 milligrams per liter

References (1)

[5] Titanium https://education.jlab.org/itselemental/ele022.html

Sources

Sources of this element.

Titanium is present in meteorites and the sun. Rocks obtained during the Apollo 17 lunar mission showed presence of 12.1% TiO2; rocks obtained during earlier Apollo missions show lower percentages.

Titanium oxide bands are prominent in the spectra of M-type stars. The element is the ninth most abundant in the crust of the earth. Titanium is almost always present in igneous rocks and in the sediments derived from them.

It occurs in the minerals rutile, ilmenite, and sphene, and is present in titanates and in many iron ores. Titanium is present in ash of coal, in plants, and in human body.

The metal was a laboratory curiosity until Kroll, in 1946, showed that titanium could be produced commercially by reducing titanium tetrachloride with magnesium. This method is still largely used for producing the metal. The metal can be purified by decomposing the iodide.

References (1)

[6] Titanium https://periodic.lanl.gov/22.shtml

References

(9)

1 PubChem

Data deposited in or computed by PubChem

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2 Atomic Mass Data Center (AMDC), International Atomic Energy Agency (IAEA)

The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.

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3 IUPAC Commission on Isotopic Abundances and Atomic Weights (CIAAW)

Titanium

Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.

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4 IUPAC Periodic Table of the Elements and Isotopes (IPTEI)

The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.

Visit source License

License note: Copyright (c) 2020 International Union of Pure and Applied Chemistry. The International Union of Pure and Applied Chemistry (IUPAC) contribution within Pubchem is provided under a CC-BY-NC-ND 4.0 license, unless otherwise stated.

5 Jefferson Lab, U.S. Department of Energy

Titanium

Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/

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License note: Please see citation and linking information: https://education.jlab.org/faq/index.html

6 Los Alamos National Laboratory, U.S. Department of Energy

Titanium

The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.

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7 NIST Physical Measurement Laboratory

Titanium

The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database

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8 PubChem Elements

Titanium

This section provides all form of data related to element Titanium.

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9 PubChem Elements

Titanium

The element property data was retrieved from publications.

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Last updated: May 1, 2026

Data verified: May 12, 2026

Content is reviewed against latest scientific data.