3.1.9. horton.periodic – Periodic table of elements

This module contains an object periodic that can be used as a Pythonic periodic table. It can be used as follows:

>>> from horton import periodic
>>> periodic['si'].number
14
>>> periodic['He'].number
2
>>> periodic['h'].symbol
'H'
>>> periodic[3].symbol
'Li'
>>> periodic['5'].symbol
'B'
class horton.periodic.Element(number=None, symbol=None, **kwargs)

Bases: object

Represents an element from the periodic table.

The following attributes are supported for all elements:

number
The atomic number.
symbol
A string with the symbol of the element.
name
The full element name.
group
The group of the element (not for actinides and lanthanides).
period
The row of the periodic system.

The following attributes are present for some elements. When a parameter is not known for a given element, the attribute is set to None.

cov_radius_cordero
Covalent radius. B. Cordero, V. Gomez, A. E. Platero-Prats, M. Reves, J. Echeverria, E. Cremades, F. Barragan, and S. Alvarez, Dalton Trans. pp. 2832–2838 (2008), URL http://dx.doi.org/10.1039/b801115j
cov_radius_bragg
Covalent radius. W. L. Bragg, Phil. Mag. 40, 169 (1920), URL http://dx.doi.org/10.1080/14786440808636111
cov_radius_slater
Covalent radius. J. C. Slater, J. Chem. Phys. 41, 3199 (1964), URL http://dx.doi.org/10.1063/1.1725697
vdw_radius_bondi
van der Waals radius. A. Bondi, J. Phys. Chem. 68, 441 (1964), URL http://dx.doi.org/10.1021/j100785a001
vdw_radius_truhlar
van der Waals radius. M. Mantina A. C. Chamberlin R. Valero C. J. Cramer D. G. Truhlar J. Phys. Chem. A 113 5806 (2009), URL http://dx.doi.org/10.1021/jp8111556
vdw_radius_rt
van der Waals radius. R. S. Rowland and R. Taylor, J. Phys. Chem. 100, 7384 (1996), URL http://dx.doi.org/10.1021/jp953141+
vdw_radius_batsanov
van der Waals radius. S. S. Batsanov Inorganic Materials 37 871 (2001), URL http://dx.doi.org/10.1023/a%3a1011625728803
vdw_radius_dreiding
van der Waals radius. Stephen L. Mayo, Barry D. Olafson, and William A. Goddard III J. Phys. Chem. 94 8897 (1990), URL http://dx.doi.org/10.1021/j100389a010
vdw_radius_uff
van der Waals radius. A. K. Rappi, C. J. Casewit, K. S. Colwell, W. A. Goddard III, and W. M. Skid J. Am. Chem. Soc. 114 10024 (1992), URL http://dx.doi.org/10.1021/ja00051a040
vdw_radius_mm3
van der Waals radius. N. L. Allinger, X. Zhou, and J. Bergsma, Journal of Molecular Structure: THEOCHEM 312, 69 (1994), http://dx.doi.org/10.1016/s0166-1280(09)80008-0
wc_radius
Waber-Cromer radius of the outermost orbital maximum. J. T. Waber and D. T. Cromer, J. Chem. Phys. 42, 4116 (1965), URL http://dx.doi.org/10.1063/1.1695904
cr_radius
Clementi-Raimondi radius. E. Clementi, D. L. Raimondi, W. P. Reinhardt, J. Chem. Phys. 47, 1300 (1967), URL http://dx.doi.org/10.1063/1.1712084
pold_crc
Isolated atom dipole polarizability. CRC Handbook of Chemistry and Physics (CRC, Boca Raton, FL, 2003). If multiple values were present in the CRC book, the value used in Erin’s postg code is taken.
pold_chu
Isolated atom dipole polarizability. X. Chu & A. Dalgarno, J. Chem. Phys., 121(9), 4083–4088 (2004), URL http://dx.doi.org/10.1063/1.1779576 Theoretical value for hydrogen from this paper: A.D. Buckingham, K.L. Clarke; Chem. Phys. Lett. 57(3), 321–325 (1978), URL http://dx.doi.org/10.1016/0009-2614(78)85517-1
c6_chu
Isolated atom C_6 dispersion coefficient. X. Chu & A. Dalgarno, J. Chem. Phys., 121(9), 4083–4088 (2004), URL http://dx.doi.org/10.1063/1.1779576 Theoretical value for hydrogen from this paper: K. T. Tang, J. M. Norbeck and P. R. Certain; J. Chem. Phys. 64, 3063 (1976), URL # http://dx.doi.org/10.1063/1.432569
mass
The IUPAC atomic masses (wieghts) of 2013. T.B. Coplen, W.A. Brand, J. Meija, M. Gröning, N.E. Holden, M. Berglund, P. De Bièvre, R.D. Loss, T. Prohaska, and T. Walczyk. http://ciaaw.org, http://www.ciaaw.org/pubs/TSAW2013_xls.xls, When ranges are provided, the middle of the range is used.

The following attributes are derived from the data given above:

cov_radius:
equals cov_radius_cordero
vdw_radius:
vdw_radius_truhlar if present
else vdw_radius_bondi if present
else vdw_radius_batsanov if present
else vdw_radius_mm3 if present
else None
becke_radius:
cov_radius_slater if present
else cov_radius_cordero if present
else None
pold:
pold_crc
c6:
c6_chu
__init__(number=None, symbol=None, **kwargs)

x.__init__(…) initializes x; see help(type(x)) for signature

class horton.periodic.Periodic(elements)

Bases: object

Arguments:

elements
A list of Element instances.
__getitem__(index)

Get an element from the table based on a flexible index.

Argument:

index
This can be either an integer atomic number, a string with the elemental symbol (any case), or a string with the atomic number.

Returns: the corresponding Element instance

__init__(elements)

Arguments:

elements
A list of Element instances.