Technetium (Tc) Elemental Symbol

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Technétium Technetium Tecneto Tecnécio Tecnecio Teknetium

Technetium Bohr ModelTechnetium is a Block D, Group 7, Period 5 element. The number of electrons in each of Technetium's shells is 2, 8, 18, 13, 2 and its electron configuration is [Kr] 4d5 5s2. The Technetium atom has a radius of and its Van der Waals radius is In its elemental form, CAS 7440-26-8, technetium has shinny gray appearance. Technetium is produced as a byproduct of the nuclear industry from spent nuclear fuel rods and was the first element to be made artificially. This is indicated by its name which originates from the Greek word "technetos" meaning artificial. Nearly all technetium is synthetically produced; however, it is found in nature in minute amounts as a result of naturally occurring spontaneous fission or neutron capture by molybdenum. Technetium was discovered by Carlo Perrier and Emilio Segre in 1937.

Technetium is used in nuclear medicine for a wide variety of diagnostic tests. Safety data for Technetium and its compounds can vary widely depending on the form. Technetium information, including technical data, safety data, high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on earth, conductivity and thermal properties are also included.

  • Properties
  • Research
  • Isotopes
  • Other Elements

Technetium Properties

Symbol: Tc Melting Point: 2157 oC, 3914.6 oF, 2430.15 K
Atomic Number: 43 Boiling Point: 4265 oC, 7709 oF, 4538.15 K
Atomic Weight: 98 Density: 11 g·cm−3
Element Category: transition metal Liquid Density @ Melting Point: N/A
Group, Period, Block: 7, 5, d Specific Heat: N/A
    Heat of Vaporization 585.2 kJ·mol−1
CHEMICAL STRUCTURE Heat of Fusion 33.29 kJ·mol−1
Electrons: 43 Thermal Conductivity: 50.6 W·m−1·K−1
Protons: 43 Thermal Expansion: N/A
Neutrons: 55 Electrical Resistivity: N/A
Electron Configuration: [Kr] 4d55s2 Electronegativity: 1.9 (Pauling scale)
Atomic Radius: 1.36 pm Tensile Strength: N/A
Covalent Radius: 147±7 pm Molar Heat Capacity: 24.27 J·mol−1·K−1
Van der Waals radius:   Young's Modulus: N/A
Oxidation States: 7, 6, 5, 4, 3, 2, 1, -1, -3 (strongly acidic oxide) Shear Modulus: N/A
Phase: Solid Bulk Modulus: N/A
Crystal Structure: hexagonal close-packed Poisson Ratio: N/A
Magnetic Ordering: Paramagnetic Mohs Hardness: N/A
1st Ionization Energy: 702.42 kJ mol-1 Vickers Hardness: N/A
2nd Ionization Energy: 702.42 kJ mol-1 Brinell Hardness: N/A
3rd Ionization Energy: 2850.20 kJ mol-1 Speed of Sound: (20 °C) 16,200 m·s−1
CAS Number: 7440-26-8 Abundance in typical human body, by weight: N/A
ChemSpider ID: 22396 Abundance in typical human body, by atom: N/A
PubChem CID: N/A Abundance in universe, by weight: N/A
MDL Number: N/A Abundance in universe, by atom: N/A
EC Number: N/A Discovered By: Carlo Perrier and Emilio Segrè
Beilstein Number: N/A Discovery Date: 1937
SMILES Identifier: [Tc]  
InChI Identifier: InChI=1S/Tc Other Names: N/A

Recent Research & Development for Technetium

  • Attenuation of apoptosis by telmisartan in atherosclerotic plaques of apolipoprotein e-/- mice: evaluation using technetium 99m-annexin a5. Zhao Y, Zhao S, Kuge Y, Strauss HW, Blankenberg FG, Tamaki N. Mol Imaging. 2013 Aug 1;12(5):300-9.
  • An estimate of the inventory of technetium-99 in the sub-tidal sediments of the Irish Sea. Jenkinson SB, McCubbin D, Kennedy PH, Dewar A, Bonfield R, Leonard KS. J Environ Radioact. 2013 Jun 8. doi:pii: S0265-931X(13)00129-X. 10.1016/j.jenvrad.2013.05.004. [Epub ahead of print]
  • Technetium 99m-Labeled VQ Peptide: A New Imaging Agent for the Early Detection of Tumors or Premalignancies. Shi J, Cui L, Jia B, Liu Z, He P, Dong C, Jin X, Zhao H, Li F, Wang F. Mol Imaging. 2013 Aug 1;12(5):318-26.
  • A novel liver function evaluation system using radiopharmacokinetic modeling of technetium-99m-DTPA-galactosyl human serum albumin. Du S, Mao Y, Tong J, Li F, Che L, Li S, Yang H, Ba J, Hu N, Xing H, Lu X, Sang X, Zhang X, Wang X, Zhong S. Nucl Med Commun. 2013 Jun 5. [Epub ahead of print]
  • Assessment of the effects of access count in percutaneous nephrolithotomy on renal functions by technetium-99m-dimercaptosuccinic Acid scintigraphy. Demirtas A, Caniklioglu M, Kula M, Sofikerim M, Akinsal EC, Ergül MA, Baydilli N, Ekemekçioglu O. ISRN Urol. 2013 May 8;2013:827121. doi: 10.1155/2013/827121. Print 2013.
  • Radio-UHPLC: A tool for rapidly determining the radiochemical purity of technetium-99m radiopharmaceuticals? Kryza D, Janier M. Appl Radiat Isot. 2013 Aug;78:72-6. doi: 10.1016/j.apradiso.2013.04.005. Epub 2013 Apr 18.
  • Excited-State Characteristics of Tetracyanidonitridorhenium(V) and -technetium(V) Complexes with N-Heteroaromatic Ligands. Ikeda H, Ito A, Sakuda E, Kitamura N, Takayama T, Sekine T, Shinohara A, Yoshimura T. Inorg Chem. 2013 Jun 3;52(11):6319-27. doi: 10.1021/ic302463v. Epub 2013 May 16.
  • A Trigonal-Prismatic Hexanuclear Technetium(II) Bromide Cluster: Solid-State Synthesis and Crystallographic and Electronic Structure. Johnstone EV, Grant DJ, Poineau F, Fox L, Forster PM, Ma L, Gagliardi L, Czerwinski KR, Sattelberger AP. Inorg Chem. 2013 May 20;52(10):5660-2. doi: 10.1021/ic400967k. Epub 2013 May 9.
  • Correlation between morphological and functional liver volume in each sector using integrated SPECT/CT imaging by computed tomography and technetium-99m galactosyl serum albumin scintigraphy in patients with various diseases who had undergone hepatectomy. Nanashima A, Abo T, Tobinaga S, Murakami G, Kido Y, Fukuda T, Tsuchiya T, Matsumoto H, Nagayasu T, Kudo T. Nucl Med Commun. 2013 Jul;34(7):652-9. doi: 10.1097/MNM.0b013e328361cd42.
  • Is diameter-axial-polar scoring predictive of renal functional damage in patients undergoing partial nephrectomy? An evaluation using technetium Tc 99m ((99) Tc(m) ) diethylene-triamine-penta-acetic acid (DTPA) glomerular filtration rate. Wang L, Li M, Chen W, Wu Z, Cai C, Xiang C, Sheng J, Liu B, Yang Q, Sun Y. BJU Int. 2013 Jun;111(8):1191-8. doi: 10.1111/bju.12108. Epub 2013 Apr 12.
  • The relationship between technetium-99m-methoxyisobutyl isonitrile parathyroid scintigraphy and hormonal and biochemical markers in suspicion of primary hyperparathyroidism. Silov G, Ozdal A, Erdogan Z, Turhal O, Karaman H. Mol Imaging Radionucl Ther. 2013 Apr;22(1):8-13. doi: 10.4274/Mirt.21931. Epub 2013 Apr 5.
  • Dose- and time-dependent effects of lipopolysaccharide on technetium-99-m-labeled diethylene-triamine pentaacetatic acid clearance, respiratory system mechanics and pulmonary inflammation. Kastis GA, Toumpanakis D, Loverdos K, Anaplioti A, Samartzis A, Argyriou P, Loudos G, Karavana V, Tzouda V, Datseris I, Rontogianni D, Roussos C, Theocharis SE, Vassilakopoulos T. Exp Biol Med (Maywood). 2013 Feb;238(2):209-22. doi: 10.1258/ebm.2012.012313.
  • Distribution and persistence of technetium-99 hexamethyl propylene amine oxime-labelled bone marrow-derived mesenchymal stem cells in experimentally induced tendon lesions after intratendinous injection and regional perfusion of the equine distal limb. Sole A, Spriet M, Padgett KA, Vaughan B, Galuppo LD, Borjesson DL, Wisner ER, Vidal MA. Equine Vet J. 2013 Feb 18. doi: 10.1111/evj.12063. [Epub ahead of print]
  • Biodistribution and preparation of technetium-99m-labeled D-D3 monoclonal antibody against pro-gastrin-releasing peptide (31?98) in mice. Hao LJ, Hong ZH, Shi YZ, Liu ZL, Zhou XL. Chin Med J (Engl). 2013 Apr;126(7):1333-6.
  • Distribution of injected technetium(99m) -labeled mesenchymal stem cells in horses with naturally occurring tendinopathy. Becerra P, Valdés Vázquez MA, Dudhia J, Fiske-Jackson AR, Neves F, Hartman NG, Smith RK. J Orthop Res. 2013 Jul;31(7):1096-102. doi: 10.1002/jor.22338. Epub 2013 Mar 18.
  • The utility and prognostic value of dipyridamole technetium-99m sestamibi myocardial perfusion imaging SPECT in predicting perioperative cardiac events following non-cardiac surgery. Asli I, Shahoseini R, Azizmohammadi Z, Javadi H, Assadi M. Perfusion. 2013 Jul;28(4):333-9. doi: 10.1177/0267659113481398. Epub 2013 Mar 12.
  • Click-to-Chelate: development of technetium and rhenium-tricarbonyl labeled radiopharmaceuticals. Kluba CA, Mindt TL. Molecules. 2013 Mar 12;18(3):3206-26. doi: 10.3390/molecules18033206.
  • Preliminary studies of acetylcholinesterase activity in the rat brain using N-phenylferrocenecarboxamide labelled by the technetium-99m. Mejri N, Said NM, Guizani S, Essouissi I, Saidi M. Nucl Med Biol. 2013 May;40(4):561-6. doi: 10.1016/j.nucmedbio.2013.01.006. Epub 2013 Mar 1.
  • Technetium-bevacizumab in a patient with bone and lung metastatic colon adenocarcinoma. Noguera EC, Palazzo E, Mayoraz MF, Diller A, Burgesser MV, Jaime A, Borello A, Avila R, Mondina JC. J Clin Oncol. 2013 Apr 10;31(11):e170-2. doi: 10.1200/JCO.2012.44.0099. Epub 2013 Mar 4. No abstract available.
  • Usefulness of examining hepatic functional volume using technetium-99m galactosyl serum albumin scintigraphy in hepatocellular carcinoma. Nanashima A, Abo T, Kudo T, Sakamoto I, Hayashi H, Murakami G, Takeshita H, Hidaka S, Kido Y, Nagayasu T.

Technetium Isotopes

Technetium has no stable isotopes (all are radioactive).