mendeleev 0.2.14

Python API with a database of atomic properties for elements in the periodic table

This package provides an API for accessing various properties of elements from the periodic table of elements.

Data

Following electronegativity scales are available either as stored values or computed on request from other properties:

• Allen

• Allred & Rochow

• Cottrell & Sutton

• Ghosh

• Gordy

• Li & Xue

• Nagle

• Martynov & Batsanov

• Mulliken

• Pauling

• Sanderson

The following data are currently available:

Name	Type	Comment	Unit	Data Source
abundance_crust	float	Abundance in the Earth’s crust	mg/kg	[8]
abundance_sea	float	Abundance in the seas	mg/L	[8]
annotation	str	Annotations regarding the data
atomic_number	int	Atomic number
atomic_radius	float	Atomic radius	pm
atomic_volume	float	Atomic volume	cm3/mol
atomic_weight	float	Atomic weight		[36], [37]
atomic_weight_uncertainty	float	Atomic volume		[36], [37]
block	int	Block in periodic table
boiling_point	float	Boiling temperature	K
c6	float	C_6 dispersion coefficient in a.u.	a.u.	[1], [2]
c6_gb	float	C_6 dispersion coefficient in a.u. (Gould & Bučko)	a.u.	[35]
covalent_radius_bragg	float	Covalent radius by Bragg	pm	[3]
covalent_radius_cordero	float	Covalent radius by Cerdero et al.	pm	[4]
covalent_radius_pyykko	float	Covalent radius by Pyykko et al.	pm	[5]
covalent_radius_slater	float	Covalent radius by Slater	pm	[6]
cpk_color	str	Element color in CPK convention	HEX	[24]
density	float	Density at 295K	g/cm3
description	str	Short description of the element
dipole_polarizability	float	Dipole polarizability	a.u.	[7]
electron_affinity	float	Electron affinity	eV	[8], [9]
electrons	int	Number of electrons
en_allen	float	Allen’s scale of electronegativity	eV	[10], [11]
en_ghosh	float	Ghosh’s scale of electronegativity		[32]
en_mulliken	float	Mulliken’s scale of electronegativity	eV	[12]
en_pauling	float	Pauling’s scale of electronegativity		[8]
econf	str	Ground state electron configuration
evaporation_heat	float	Evaporation heat	kJ/mol
fusion_heat	float	Fusion heat	kJ/mol
gas_basicity	float	Gas basicity	kJ/mol	[8]
group	int	Group in periodic table
heat_of_formation	float	Heat of formation	kJ/mol	[8]
ionenergy	tuple	Ionization energies	eV	[13]
ionic_radii	list	Ionic and crystal radii in pm	pm	[14]
is_monoisotopic	bool	Is the element monoisotopic
is_radioactive	bool	Is the element radioactive
isotopes	list	Isotopes
jmol_color	str	Element color in Jmol convention	HEX	[25]
lattice_constant	float	Lattice constant	Angstrom
lattice_structure	str	Lattice structure code
mass_number	int	Mass number (most abundant isotope)
melting_point	float	Melting temperature	K
molcas_gv_color	str	Element color in MOCAS GV convention	HEX	[26]
name	str	Name in English
neutrons	int	Number of neutrons (most abundant isotope)
oxistates	list	Oxidation states
period	int	Period in periodic table
proton_affinity	float	Proton affinity	kJ/mol	[8]
protons	int	Number of protons
sconst	float	Nuclear charge screening constants		[15], [16]
series	int	Index to chemical series
specific_heat	float	Specific heat @ 20 C	J/(g mol)
symbol	str	Chemical symbol
thermal_conductivity	float	Thermal conductivity @25 C	W/(m K)
vdw_radius	float	Van der Waals radius	pm	[8]
vdw_radius_alvarez	float	Van der Waals radius according to Alvarez	pm	[33], [34]
vdw_radius_batsanov	float	Van der Waals radius according to Batsanov	pm	[17]
vdw_radius_bondi	float	Van der Waals radius according to Bondi	pm	[18]
vdw_radius_dreiding	float	Van der Waals radius from the DREIDING FF	pm	[19]
vdw_radius_mm3	float	Van der Waals radius from the MM3 FF	pm	[20]
vdw_radius_rt	float	Van der Waals radius according to Rowland and Taylor	pm	[21]
vdw_radius_truhlar	float	Van der Waals radius according to Truhlar	pm	[22]
vdw_radius_uff	float	Van der Waals radius from the UFF	pm	[23]

[1]

Chu, X., & Dalgarno, A. (2004). Linear response time-dependent density functional theory for van der Waals coefficients. The Journal of Chemical Physics, 121(9), 4083. doi:10.1063/1.1779576

[2]

Tang, K. T., Norbeck, J. M., & Certain, P. R. (1976). Upper and lower bounds of two- and three-body dipole, quadrupole, and octupole van der Waals coefficients for hydrogen, noble gas, and alkali atom interactions. The Journal of Chemical Physics, 64(7), 3063. doi:10.1063/1.432569

[3]

Bragg, W. L. (1920). The arrangement of atoms in crystals. Philosophical Magazine, 40(236), 169-189. doi:10.1080/14786440808636111

[4]

Cordero, B., Gomez, V., Platero-Prats, A. E., Reves, M., Echeverria, J., Cremades, E., … Alvarez, S. (2008). Covalent radii revisited. Dalton Transactions, (21), 2832. doi:10.1039/b801115j

[5]

Pyykko, P., & Atsumi, M. (2009). Molecular Single-Bond Covalent Radii for Elements 1-118. Chemistry - A European Journal, 15(1), 186-197. doi:10.1002/chem.200800987

[6]

Slater, J. C. (1964). Atomic Radii in Crystals. The Journal of Chemical Physics, 41(10), 3199. doi:10.1063/1.1725697

[7]

P. Schwerdtfeger “Table of experimental and calculated static dipole polarizabilities for the electronic ground states of the neutral elements (in atomic units)”, February 11, 2014 source

[8] (1,2,3,4,5,6,7,8)

W. M. Haynes, Handbook of Chemistry and Physics 95th Edition, CRC Press, New York, 2014, ISBN-10: 1482208679, ISBN-13: 978-1482208672.

[9]

Andersen, T. (2004). Atomic negative ions: structure, dynamics and collisions. Physics Reports, 394(4-5), 157-313. doi:10.1016/j.physrep.2004.01.001

[10]

Mann, J. B., Meek, T. L., & Allen, L. C. (2000). Configuration Energies of the Main Group Elements. Journal of the American Chemical Society, 122(12), 2780-2783. doi:10.1021/ja992866e

[11]

Mann, J. B., Meek, T. L., Knight, E. T., Capitani, J. F., & Allen, L. C. (2000). Configuration Energies of the d-Block Elements. Journal of the American Chemical Society, 122(21), 5132-5137. doi:10.1021/ja9928677

[12]

Mulliken, R. S. (1934). A New Electroaffinity Scale; Together with Data on Valence States and on Valence Ionization Potentials and Electron Affinities. The Journal of Chemical Physics, 2(11), 782. doi:10.1063/1.1749394

[13]

NIST Atomic Database accessed on April 13, 2015

[14]

Shannon, R. D. (1976). Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallographica Section A. doi:10.1107/S0567739476001551

[15]

Clementi, E., & Raimondi, D. L. (1963). Atomic Screening Constants from SCF Functions. The Journal of Chemical Physics, 38(11), 2686. doi:10.1063/1.1733573

[16]

Clementi, E. (1967). Atomic Screening Constants from SCF Functions. II. Atoms with 37 to 86 Electrons. The Journal of Chemical Physics, 47(4), 1300. doi:10.1063/1.1712084

[17]

Batsanov, S. S. (2001). Van der Waals radii of elements. Inorganic Materials, 37(9), 871-885. doi:10.1023/A:1011625728803

[18]

Bondi, A. (1964). van der Waals Volumes and Radii. The Journal of Physical Chemistry, 68(3), 441-451. doi:10.1021/j100785a001

[19]

Mayo, S. L., Olafson, B. D., & Goddard, W. A. (1990). DREIDING: a generic force field for molecular simulations. The Journal of Physical Chemistry, 94(26), 8897-8909. doi:10.1021/j100389a010

[20]

Allinger, N. L., Zhou, X., & Bergsma, J. (1994). Molecular mechanics parameters. Journal of Molecular Structure: THEOCHEM, 312(1), 69-83. doi:10.1016/S0166-1280(09)80008-0

[21]

Rowland, R. S., & Taylor, R. (1996). Intermolecular Nonbonded Contact Distances in Organic Crystal Structures: Comparison with Distances Expected from van der Waals Radii. The Journal of Physical Chemistry, 100(18), 7384-7391. doi:10.1021/jp953141+

[22]

Mantina, M., Chamberlin, A. C., Valero, R., Cramer, C. J., & Truhlar, D. G. (2009). Consistent van der Waals Radii for the Whole Main Group. The Journal of Physical Chemistry A, 113(19), 5806-5812. doi:10.1021/jp8111556

[23]

Rappe, A. K., Casewit, C. J., Colwell, K. S., Goddard, W. A., & Skiff, W. M. (1992). UFF, a full periodic table force field for molecular mechanics and molecular dynamics simulations. Journal of the American Chemical Society, 114(25), 10024-10035. doi:10.1021/ja00051a040

[24]

CPK colors

[25]

Jmol colors

[26]

MOLCAS GV colors

[27]

R. T. Sanderson, Chemical Bonds and Bond Energy, Academic Press, New York, 1976, ISBN: 0-12-618060-1

[28]

Allen, L. C., & Huheey, J. E. (1980). The definition of electronegativity and the chemistry of the noble gases. Journal of Inorganic and Nuclear Chemistry, 42(10), 1523-1524. doi:10.1016/0022-1902(80)80132-1

[29]

Luo, Z., Chen, X., Li, J., & Ning, C. (2016). Precision measurement of the electron affinity of niobium. Physical Review A, 93(2), 020501. doi:10.1103/PhysRevA.93.020501

[30]

Chen, X., & Ning, C. (2016). Accurate electron affinity of Co and fine-structure splittings of Co$^-$ via slow-electron velocity-map imaging. Physical Review A, 93(5), 052508. doi:10.1103/PhysRevA.93.052508

[31]

Chen, X., & Ning, C. (2016). Accurate electron affinity of Pb and isotope shifts of binding energies of Pb−. The Journal of Chemical Physics, 145(8), 84303. doi:10.1063/1.4961654

[32]

Ghosh, D. C. (2005). A New Scale of Electronegativity Based on Absolute Radii of Atoms. Journal of Theoretical and Computational Chemistry, 4(1), 21–33. doi:10.1142/S0219633605001556

[33]

Alvarez, S. (2013). A cartography of the van der Waals territories. Dalton Transactions, 42(24), 8617. doi:10.1039/c3dt50599e

[34]

Vogt, J., & Alvarez, S. (2014). van der Waals Radii of Noble Gases. Inorganic Chemistry, 53(17), 9260–9266. doi:10.1021/ic501364h

[35]

Gould, T., & Bučko, T. (2016). C 6 Coefficients and Dipole Polarizabilities for All Atoms and Many Ions in Rows 1–6 of the Periodic Table. Journal of Chemical Theory and Computation, 12(8), 3603–3613. doi:10.1021/acs.jctc.6b00361

[36] (1,2)

Meija, J., Coplen, T. B., Berglund, M., Brand, W. A., De Bièvre, P., Gröning, M., Holden, N., Irrgeher, J., Loss, R., Walczyk, T., Prohaska, T. (2016). Atomic weights of the elements 2013 (IUPAC Technical Report). Pure and Applied Chemistry, 88(3), 265–291. doi:10.1515/pac-2015-0305

[37] (1,2)

Standard Atomic Weights, IUPAC-CIAAW, http://www.ciaaw.org/atomic-weights.htm accessed Jan. 1st 2017.

Installation

The package can be installed using pip

pip install mendeleev

You can also install the most recent version from the repository:

pip install https://bitbucket.org/lukaszmentel/mendeleev/get/tip.tar.gz

Usage

The simple interface to the data is through the element method that returns the Element objects:

>>> from mendeleev import element

The element method accepts unique identifiers: atomic number, atomic symbol or element’s name in english. To retrieve the entries on Silicon by symbol type

>>> si = element('Si')
>>> si
Element(
    annotation=u'',
    atomic_number=14,
    atomic_radius=132.0,
    atomic_volume=12.1,
    block=u'p',
    boiling_point=2628.0,
    covalent_radius_2008=111.00000000000001,
    covalent_radius_2009=115.99999999999999,
    density=2.33,
    description=u"Metalloid element belonging to group 14 of the periodic table. It is the second most abundant element in the Earth's crust, making up 25.7% of it by weight. Chemically less reactive than carbon. First identified by Lavoisier in 1787 and first isolated in 1823 by Berzelius.",
    dipole_polarizability=37.31,
    ec=1s2 2s2 2p6 3s2 3p2,
    econf=u'[Ne] 3s2 3p2',
    electron_affinity=1.3895211,
    en_allen=11.33,
    en_pauling=1.9,
    evaporation_heat=383.0,
    fusion_heat=50.6,
    group_id=14,
    lattice_constant=5.43,
    lattice_structure=u'DIA',
    mass=28.0855,
    melting_point=u'1683',
    name=u'Silicon',
    period=3,
    specific_heat=0.703,
    symbol=u'Si',
    thermal_conductivity=149.0,
    vdw_radius=210.0,
)

Similarly to access the data by atomic number or element names type

>>> al = element(13)
>>> al.name
'Aluminium'
>>> o = element('Oxygen')
>>> o.atomic_number
8

Lists of elements

The element method also accepts list or tuple of identifiers and then returns a list of Element objects

>>> c, h, o = element(['C', 'Hydrogen', 8])
>>> c.name, h.name, o.name
('Carbon', 'Hydrogen', 'Oxygen')

Composite Attributes

Currently four of the attributes are more complex object than str, int or float, those are:

• oxistates, returns a list of oxidation states

• ionenergies, returns a dictionary of ionization energies

• isotopes, returns a list of Isotope objects

• ionic_radii returns a list of IonicRadius objects

Oxidation states

For examples oxistates returns a list of oxidation states for a given element

>>> fe = element('Fe')
>>> fe.oxistates
[6, 3, 2, 0, -2]

Ionization energies

The ionenergies returns a dictionary with ionization energies as values and degrees of ionization as keys.

>>> fe = element('Fe')
>>> fe.ionenergies
{1: 7.9024678,
 2: 16.1992,
 3: 30.651,
 4: 54.91,
 5: 75.0,
 6: 98.985,
 7: 125.0,
 8: 151.06,
 9: 233.6,
 10: 262.1,
 11: 290.9,
 12: 330.81,
 13: 361.0,
 14: 392.2,
 15: 456.2,
 16: 489.312,
 17: 1262.7,
 18: 1357.8,
 19: 1460.0,
 20: 1575.6,
 21: 1687.0,
 22: 1798.43,
 23: 1950.4,
 24: 2045.759,
 25: 8828.1875,
 26: 9277.681}

Isotopes

The isotopes attribute returns a list of Isotope objects with the following attributes per isotope

• atomic_number

• mass

• abundance

• mass_number

>>> fe = element('Fe')
>>> for iso in fe.isotopes:
...     print(iso)
 26   55.93494  91.75%    56
 26   56.93540   2.12%    57
 26   57.93328   0.28%    58
 26   53.93961   5.85%    54

The columns represent the attributes atomic_number, mass, abundance and mass_number respectively.

Ionic radii

Another composite attribute is ionic_radii which returns a list of IonicRadius object with the following attributes

• atomic_number, atomic number of the ion

• charge, charge of the ion

• econf, electronic configuration of the ion

• coordination, coordination type of the ion

• spin, spin state of the ion (HS or LS)

• crystal_radius

• ionic_radius

• origin, source of the data

• most_reliable, recommended value

>>> fe = element('Fe')
>>> for ir in fe.ionic_radii:
...     print(ir)
charge=   2, coordination=IV   , crystal_radius= 0.770, ionic_radius= 0.630
charge=   2, coordination=IVSQ , crystal_radius= 0.780, ionic_radius= 0.640
charge=   2, coordination=VI   , crystal_radius= 0.750, ionic_radius= 0.610
charge=   2, coordination=VI   , crystal_radius= 0.920, ionic_radius= 0.780
charge=   2, coordination=VIII , crystal_radius= 1.060, ionic_radius= 0.920
charge=   3, coordination=IV   , crystal_radius= 0.630, ionic_radius= 0.490
charge=   3, coordination=V    , crystal_radius= 0.720, ionic_radius= 0.580
charge=   3, coordination=VI   , crystal_radius= 0.690, ionic_radius= 0.550
charge=   3, coordination=VI   , crystal_radius= 0.785, ionic_radius= 0.645
charge=   3, coordination=VIII , crystal_radius= 0.920, ionic_radius= 0.780
charge=   4, coordination=VI   , crystal_radius= 0.725, ionic_radius= 0.585
charge=   6, coordination=IV   , crystal_radius= 0.390, ionic_radius= 0.250

CLI utility

For those who work in the terminal there is a simple command line interface (CLI) for printing the information about a given element. The script name is element.py and it accepts either the symbol or name of the element as an argument and prints the data about it. For example, to print the properties of silicon type

$ element.py Si
   _  _  _  _      _
 _(_)(_)(_)(_)_   (_)
(_)          (_)_  _
(_)_  _  _  _  (_)(_)
  (_)(_)(_)(_)_   (_)
 _           (_)  (_)
(_)_  _  _  _(_)_ (_)
  (_)(_)(_)(_) (_)(_)(_)



Description
===========

  Metalloid element belonging to group 14 of the periodic table. It is
  the second most abundant element in the Earth's crust, making up 25.7%
  of it by weight. Chemically less reactive than carbon. First
  identified by Lavoisier in 1787 and first isolated in 1823 by
  Berzelius.

Properties
==========

Annotation
Atomic number                       14
Atomic radius                      132
Atomic volume                     12.1
Block                                p
Boiling point                     2628
Covalent radius 2008               111
Covalent radius 2009               116
Cpk color                      #daa520
Density                           2.33
Dipole polarizability            37.31
Electron affinity              1.38952
Electronic configuration  [Ne] 3s2 3p2
En allen                         11.33
En pauling                         1.9
Evaporation heat                   383
Fusion heat                       50.6
Gas basicity                     814.1
Group id                            14
Heat of formation                  450
Jmol color                     #f0c8a0
Lattice constant                  5.43
Lattice structure                  DIA
Mass                           28.0855
Melting point                     1683
Name                           Silicon
Period                               3
Proton affinity                    837
Series id                            5
Specific heat                    0.703
Symbol                              Si
Thermal conductivity               149
Vdw radius                         210

Documentation

Documentation can be found here.

Citing

If you use mendeleev in a scientific publication, please cite the software as

L. M. Mentel, mendeleev, 2014. Available at: https://bitbucket.org/lukaszmentel/mendeleev.

Funding

This project is supported by the RCN (The Research Council of Norway) project number 239193.