##################################################################
## (c) Copyright 2015- by Jaron T. Krogel ##
##################################################################
"""Classes and methods for getting data and properties of elements."""
from __future__ import annotations
from dataclasses import dataclass
from enum import Enum
from .developer import warn
[docs]
@dataclass(frozen=True)
class ElementData:
"""Dataclass for storing element data."""
symbol: str
atomic_number: int
atomic_weight: float
group: int
isotopes: dict[int, float]
def __hash__(self):
return hash((
self.symbol,
self.atomic_number,
self.atomic_weight,
self.group,
tuple(self.isotopes.keys()),
tuple(self.isotopes.values()),
))
[docs]
def principle_isotope(self) -> tuple[int, float]:
"""Get the mass number and relative atomic weight of the most common isotope.
Isotopic abundances defined by NIST [1]_.
Returns
-------
mass_number : int
Mass number of the most common isotope.
relative_atomic_mass : float
The relative atomic mass of the isotope.
References
----------
.. [1] https://www.nist.gov/pml/atomic-weights-and-isotopic-compositions-relative-atomic-masses
"""
mass_number = list(self.isotopes.keys())[0]
return mass_number, self.isotopes[mass_number]
[docs]
def protons(self) -> int:
"""Alias for ``self.atomic_number``."""
return self.atomic_number
[docs]
def neutrons(self, mass_number: int | None = None) -> int:
"""Get the number of neutrons for the isotope with the given mass number.
If no mass number is provided, this defaults to the most common isotope.
Warns
-----
NexusWarning
If mass number is not in the known isotopes for the element.
"""
if mass_number is None:
mass_number = self.principle_isotope()[0]
elif mass_number not in self.isotopes.keys():
warn(
f"Mass number {mass_number} is not in the known isotopes for {self.name}.\n"
"Will proceed with given mass number, but you may want to check your inputs!"
)
return mass_number - self.atomic_number
#end class ElementData
[docs]
class Elements(ElementData, Enum):
"""Enumeration of all elements in the periodic table.
Attributes
----------
symbol : str
In titlecase (H, He, ...)
atomic_number : int
Use 0 for a dummy element
(symbol "Xx", name "Unknown", all properties zero)
atomic_weight : float
Average atomic weight in amu [1]_.
group : int
Group of the element on the periodic table.
Lanthanides and Actinides are 0.
isotopes : dict[int, float]
A dictionary of the isotopes for the element [2]_.
This can be accessed as ``Element.Name.isotopes[mass_number]``,
which yields the relative atomic mass.
These dictionaries are sorted in order of decreasing isotopic
abundance, as defined by NIST [2]_. The code to generate the
isotope dictionaries can be found at
https://github.com/QMCPACK/qmcpack/pull/6006.
References
----------
.. [1] https://iupac.qmul.ac.uk/AtWt/
.. [2] https://www.nist.gov/pml/atomic-weights-and-isotopic-compositions-relative-atomic-masses
Examples
--------
The fastest way to grab element data is with the following signatures:
>>> Elements("Hydrogen") is Elements.Hydrogen
True
>>> Elements("H") is Elements.Hydrogen
True
>>> Elements(1) is Elements.Hydrogen
True
If you're unsure of the case of the input you can reliably get
case-insensitive parsing with the default interface.
>>> Elements("h") is Elements.Hydrogen
True
>>> Elements("hydrogen") is Elements.Hydrogen
True
It can also handle leading and trailing whitespace
>>> Elements("Hydrogen ") is Elements.Hydrogen
True
>>> Elements(" H") is Elements.Hydrogen
True
If you think the input is up to **one** step from the correct
signature, (e.g. ``Elements(int(val))``) you can still expect the
default call to work.
>>> Elements("1") is Elements.Hydrogen
True
>>> Elements(1.0) is Elements.Hydrogen
True
Printing an element calls its ``__str__`` method which will return
just the atomic symbol.
>>> print(Elements.Hydrogen)
H
This also works with f-strings and ``str.format`` calls.
>>> print(f"{Elements.Hydrogen}")
H
If you want to see the data attached to the enum member
(minus the isotopes), use ``repr``.
>>> print(repr(Elements.Hydrogen))
<Elements.Hydrogen: symbol='H', atomic_number=1, atomic_weight=1.008, group=1>
You can also get this view by just directly typing the element.
>>> Elements.Hydrogen
<Elements.Hydrogen: symbol='H', atomic_number=1, atomic_weight=1.008, group=1>
All functions defined for ``ElementData`` are accessible for members
of this enum.
>>> Elements.Carbon.protons()
6
>>> Elements.Carbon.neutrons()
6
>>> Elements.Carbon.neutrons(mass_number=13)
7
>>> Elements.Carbon.most_common_isotope()
(12, 12.0)
"""
def __new__(
cls,
symbol: str,
atomic_number: int,
atomic_weight: float,
group: int,
isotopes: dict[int, float]
):
element = ElementData.__new__(cls)
element._value_ = atomic_number
return element
# Override to not print isotopes
def __repr__(self):
# This prints on one line, but since it's nearly impossible to
# grep for this regardless of if it's on one line in the code
# it is split here for readability.
return (
f"<{self.__class__.__name__}.{self.name}: "
f"symbol='{self.symbol}', "
f"atomic_number={self.atomic_number}, "
f"atomic_weight={self.atomic_weight}, "
f"group={self.group}>"
)
def __str__(self) -> str:
return self.symbol
@classmethod
def _missing_(cls, value):
"""Workaround to not having access to ``_add_alias_`` or
``_add_value_alias_`` from Python 3.13. This function
automatically gets called when the traditional lookup fails.
"""
if isinstance(value, str):
value = value.strip()
if value.isalpha(): # `Elements("h")` or `Elements("hydrogen")`
val_title = value.title()
if val_title in cls.__members__:
return cls.__members__[val_title]
elif value.isdecimal(): # `Elements("1")`
try:
value = int(value)
except ValueError: # We don't support `Elements("1.0")`
pass
if isinstance(value, int) and value <= cls.num_elements():
return cls._value2member_map_[value]
raise ValueError(f"Can not determine element for input value: {value}!")
[docs]
@staticmethod
def is_element(
value: str,
return_element: bool = False,
) -> bool | tuple[bool, Elements]:
"""Robust method that will try to match a wide array of element
identifier formats, including all that are handled by the parent
call signature ``Elements(value)``.
Parameters
----------
value : str
The string to be checked.
return_element : bool, default=False
Return the element that was identified.
This will return ``value`` if it could not be identified as
an element.
Examples
--------
Regular elements
>>> Elements.is_element("H")
True
>>> Elements.is_element("He")
True
Elements with integer identifiers
>>> Elements.is_element("H1")
True
>>> Elements.is_element("H10")
True
>>> Elements.is_element("He1")
True
>>> Elements.is_element("He10")
True
Elements with integer identifiers and underscores
>>> Elements.is_element("H_1")
True
>>> Elements.is_element("H_10")
True
>>> Elements.is_element("He_1")
True
>>> Elements.is_element("He_10")
True
Elements with integer identifiers and hyphens
>>> Elements.is_element("H-1")
True
>>> Elements.is_element("H-10")
True
>>> Elements.is_element("He-1")
True
>>> Elements.is_element("He-10")
True
You can optionally return the element as well
>>> Elements.is_element("H_10", return_element=True)
(True, <Elements.Hydrogen: symbol='H', atomic_number=1, atomic_weight=1.008, group=1>)
>>> Elements.is_element("He-1", return_element=True)
(True, <Elements.Helium: symbol='He', atomic_number=2, atomic_weight=4.002602, group=18>)
If it can't determine the element and you asked it to return the
element then it will return ``False`` and the supplied value.
>>> Elements.is_element("Bean", return_element=True)
(False, 'Bean')
"""
if isinstance(value, Elements):
if return_element:
return True, value
else:
return True
val_len = len(value)
if "_" in value: # H_1
value = value.split("_", maxsplit=1)[0]
elif "-" in value: # H-1
value = value.split("-", maxsplit=1)[0]
elif val_len >= 2 and value[1:].isdigit(): # H1 / H10
value = value[0:1]
elif val_len >= 3 and value[2:].isdigit(): # He1 / He10
value = value[0:2]
value = value.title()
if value in Elements.__members__:
if return_element:
return True, Elements(value)
else:
return True
else:
if return_element:
return False, value
else:
return False
[docs]
@staticmethod
def num_elements() -> int:
return len(Elements) - 1 # Dummy atom
# Name Symbol Number Mass Group Isotopes
Unknown = "Xx", 0, 0.0, 0, { 0:0.0}
Hydrogen = "H", 1, 1.0080, 1, { 1: 1.00782503223, 2: 2.01410177812, 3: 3.0160492779}
Helium = "He", 2, 4.002602, 18, { 4: 4.00260325413, 3: 3.0160293201}
Lithium = "Li", 3, 6.94, 1, { 7: 7.0160034366, 6: 6.0151228874}
Beryllium = "Be", 4, 9.0121831, 2, { 9: 9.012183065}
Boron = "B", 5, 10.81, 13, { 11: 11.00930536, 10: 10.01293695}
Carbon = "C", 6, 12.011, 14, { 12: 12.0, 13: 13.00335483507, 14: 14.0032419884}
Nitrogen = "N", 7, 14.007, 15, { 14: 14.00307400443, 15: 15.00010889888}
Oxygen = "O", 8, 15.999, 16, { 16: 15.99491461957, 18: 17.99915961286, 17: 16.9991317565}
Fluorine = "F", 9, 18.998403162, 17, { 19: 18.99840316273}
Neon = "Ne", 10, 20.1797, 18, { 20: 19.9924401762, 22: 21.991385114, 21: 20.993846685}
Sodium = "Na", 11, 22.98976928, 1, { 23: 22.989769282}
Magnesium = "Mg", 12, 24.305, 2, { 24: 23.985041697, 26: 25.982592968, 25: 24.985836976}
Aluminum = "Al", 13, 26.9815384, 13, { 27: 26.98153853}
Silicon = "Si", 14, 28.085, 14, { 28: 27.97692653465, 29: 28.9764946649, 30: 29.973770136}
Phosphorus = "P", 15, 30.973761998, 15, { 31: 30.97376199842}
Sulfur = "S", 16, 32.06, 16, { 32: 31.9720711744, 34: 33.967867004, 33: 32.9714589098, 36: 35.96708071}
Chlorine = "Cl", 17, 35.45, 17, { 35: 34.968852682, 37: 36.965902602}
Argon = "Ar", 18, 39.95, 18, { 40: 39.9623831237, 36: 35.967545105, 38: 37.96273211}
Potassium = "K", 19, 39.0983, 1, { 39: 38.9637064864, 41: 40.9618252579, 40: 39.963998166}
Calcium = "Ca", 20, 40.078, 2, { 40: 39.962590863, 44: 43.95548156, 42: 41.95861783, 48: 47.95252276, 43: 42.95876644, 46: 45.953689}
Scandium = "Sc", 21, 44.955907, 3, { 45: 44.95590828}
Titanium = "Ti", 22, 47.867, 4, { 48: 47.94794198, 46: 45.95262772, 47: 46.95175879, 49: 48.94786568, 50: 49.94478689}
Vanadium = "V", 23, 50.9415, 5, { 51: 50.94395704, 50: 49.94715601}
Chromium = "Cr", 24, 51.9961, 6, { 52: 51.94050623, 53: 52.94064815, 50: 49.94604183, 54: 53.93887916}
Manganese = "Mn", 25, 54.938043, 7, { 55: 54.93804391}
Iron = "Fe", 26, 55.845, 8, { 56: 55.93493633, 54: 53.93960899, 57: 56.93539284, 58: 57.93327443}
Cobalt = "Co", 27, 58.933194, 9, { 59: 58.93319429}
Nickel = "Ni", 28, 58.6934, 10, { 58: 57.93534241, 60: 59.93078588, 62: 61.92834537, 61: 60.93105557, 64: 63.92796682}
Copper = "Cu", 29, 63.546, 11, { 63: 62.92959772, 65: 64.9277897}
Zinc = "Zn", 30, 65.38, 12, { 64: 63.92914201, 66: 65.92603381, 68: 67.92484455, 67: 66.92712775, 70: 69.9253192}
Gallium = "Ga", 31, 69.723, 13, { 69: 68.9255735, 71: 70.92470258}
Germanium = "Ge", 32, 72.630, 14, { 74: 73.921177761, 72: 71.922075826, 70: 69.92424875, 73: 72.923458956, 76: 75.921402726}
Arsenic = "As", 33, 74.921595, 15, { 75: 74.92159457}
Selenium = "Se", 34, 78.971, 16, { 80: 79.9165218, 78: 77.91730928, 76: 75.919213704, 82: 81.9166995, 77: 76.919914154, 74: 73.922475934}
Bromine = "Br", 35, 79.904, 17, { 79: 78.9183376, 81: 80.9162897}
Krypton = "Kr", 36, 83.798, 18, { 84: 83.9114977282, 86: 85.9106106269, 82: 81.91348273, 83: 82.91412716, 80: 79.91637808, 78: 77.92036494}
Rubidium = "Rb", 37, 85.4678, 1, { 85: 84.9117897379, 87: 86.909180531}
Strontium = "Sr", 38, 87.62, 2, { 88: 87.9056125, 86: 85.9092606, 87: 86.9088775, 84: 83.9134191}
Yttrium = "Y", 39, 88.905838, 3, { 89: 88.9058403}
Zirconium = "Zr", 40, 91.222, 4, { 90: 89.9046977, 94: 93.9063108, 92: 91.9050347, 91: 90.9056396, 96: 95.9082714}
Niobium = "Nb", 41, 92.90637, 5, { 93: 92.906373}
Molybdenum = "Mo", 42, 95.95, 6, { 98: 97.90540482, 96: 95.90467612, 95: 94.90583877, 92: 91.90680796, 100:99.9074718, 97: 96.90601812, 94: 93.9050849}
Technetium = "Tc", 43, 97.0, 7, { 97: 96.9063667, 98: 97.9072124, 99: 98.9062508}
Ruthenium = "Ru", 44, 101.07, 8, {102:101.9043441, 104:103.9054275, 101:100.9055769, 99: 98.9059341, 100:99.9042143, 96: 95.90759025, 98: 97.9052868}
Rhodium = "Rh", 45, 102.90549, 9, {103:102.905498}
Palladium = "Pd", 46, 106.42, 10, {106:105.9034804, 108:107.9038916, 105:104.9050796, 110:109.9051722, 104:103.9040305, 102:101.9056022}
Silver = "Ag", 47, 107.8682, 11, {107:106.9050916, 109:108.9047553}
Cadmium = "Cd", 48, 112.414, 12, {114:113.90336509, 112:111.90276287, 111:110.90418287, 110:109.90300661, 113:112.90440813, 116:115.90476315, 106:105.9064599, 108:107.9041834}
Indium = "In", 49, 114.818, 13, {115:114.903878776, 113:112.90406184}
Tin = "Sn", 50, 118.710, 14, {120:119.90220163, 118:117.90160657, 116:115.9017428, 119:118.90331117, 117:116.90295398, 124:123.9052766, 122:121.9034438, 112:111.90482387, 114:113.9027827, 115:114.903344699}
Antimony = "Sb", 51, 121.760, 15, {121:120.903812, 123:122.9042132}
Tellurium = "Te", 52, 127.60, 16, {130:129.906222748, 128:127.90446128, 126:125.9033109, 125:124.9044299, 124:123.9028171, 122:121.9030435, 123:122.9042698, 120:119.9040593}
Iodine = "I", 53, 126.90447, 17, {127:126.9044719}
Xenon = "Xe", 54, 131.293, 18, {132:131.9041550856, 129:128.9047808611, 131:130.90508406, 134:133.90539466, 136:135.907214484, 130:129.903509349, 128:127.903531, 124:123.905892, 126:125.9042983}
Cesium = "Cs", 55, 132.90545196, 1, {133:132.905451961}
Barium = "Ba", 56, 137.327, 2, {138:137.905247, 137:136.90582714, 136:135.90457573, 135:134.90568838, 134:133.90450818, 130:129.9063207, 132:131.9050611}
Lanthanum = "La", 57, 138.90547, 3, {139:138.9063563, 138:137.9071149}
Cerium = "Ce", 58, 140.116, 0, {140:139.9054431, 142:141.9092504, 138:137.905991, 136:135.90712921}
Praseodymium = "Pr", 59, 140.90766, 0, {141:140.9076576}
Neodymium = "Nd", 60, 144.242, 0, {142:141.907729, 144:143.910093, 146:145.9131226, 143:142.90982, 145:144.9125793, 148:147.9168993, 150:149.9209022}
Promethium = "Pm", 61, 145.0, 0, {145:144.9127559, 147:146.915145}
Samarium = "Sm", 62, 150.36, 0, {152:151.9197397, 154:153.9222169, 147:146.9149044, 149:148.9171921, 148:147.9148292, 150:149.9172829, 144:143.9120065}
Europium = "Eu", 63, 151.964, 0, {153:152.921238, 151:150.9198578}
Gadolinium = "Gd", 64, 157.249, 0, {158:157.9241123, 160:159.9270624, 156:155.9221312, 157:156.9239686, 155:154.9226305, 154:153.9208741, 152:151.9197995}
Terbium = "Tb", 65, 158.925354, 0, {159:158.9253547}
Dysprosium = "Dy", 66, 162.500, 0, {164:163.9291819, 162:161.9268056, 163:162.9287383, 161:160.9269405, 160:159.9252046, 158:157.9244159, 156:155.9242847}
Holmium = "Ho", 67, 164.930329, 0, {165:164.9303288}
Erbium = "Er", 68, 167.259, 0, {166:165.9302995, 168:167.9323767, 167:166.9320546, 170:169.9354702, 164:163.9292088, 162:161.9287884}
Thulium = "Tm", 69, 168.934219, 0, {169:168.9342179}
Ytterbium = "Yb", 70, 173.045, 0, {174:173.9388664, 172:171.9363859, 173:172.9382151, 171:170.9363302, 176:175.9425764, 170:169.9347664, 168:167.9338896}
Lutetium = "Lu", 71, 174.96669, 0, {175:174.9407752, 176:175.9426897}
Hafnium = "Hf", 72, 178.486, 4, {180:179.946557, 178:177.9437058, 177:176.9432277, 179:178.9458232, 176:175.9414076, 174:173.9400461}
Tantalum = "Ta", 73, 180.94788, 5, {181:180.9479958, 180:179.9474648}
Tungsten = "W", 74, 183.84, 6, {184:183.95093092, 186:185.9543628, 182:181.94820394, 183:182.95022275, 180:179.9467108}
Rhenium = "Re", 75, 186.207, 7, {187:186.9557501, 185:184.9529545}
Osmium = "Os", 76, 190.23, 8, {192:191.961477, 190:189.9584437, 189:188.9581442, 188:187.9558352, 187:186.9557474, 186:185.953835, 184:183.9524885}
Iridium = "Ir", 77, 192.217, 9, {193:192.9629216, 191:190.9605893}
Platinum = "Pt", 78, 195.084, 10, {195:194.9647917, 194:193.9626809, 196:195.96495209, 198:197.9678949, 192:191.9610387, 190:189.9599297}
Gold = "Au", 79, 196.966570, 11, {197:196.96656879}
Mercury = "Hg", 80, 200.592, 12, {202:201.9706434, 200:199.96832659, 199:198.96828064, 201:200.97030284, 198:197.9667686, 204:203.97349398, 196:195.9658326}
Thallium = "Tl", 81, 204.38, 13, {205:204.9744278, 203:202.9723446}
Lead = "Pb", 82, 207.2, 14, {208:207.9766525, 206:205.9744657, 207:206.9758973, 204:203.973044}
Bismuth = "Bi", 83, 208.98040, 15, {209:208.9803991}
Polonium = "Po", 84, 209.0, 16, {209:208.9824308, 210:209.9828741}
Astatine = "At", 85, 210.0, 17, {210:209.9871479, 211:210.9874966}
Radon = "Rn", 86, 222.0, 18, {211:210.9906011, 220:220.0113941, 222:222.0175782}
Francium = "Fr", 87, 223.0, 1, {223:223.019736}
Radium = "Ra", 88, 226.0, 2, {223:223.0185023, 224:224.020212, 226:226.0254103, 228:228.0310707}
Actinium = "Ac", 89, 227.0, 3, {227:227.0277523}
Thorium = "Th", 90, 232.0377, 0, {232:232.0380558, 230:230.0331341}
Protactinium = "Pa", 91, 231.03588, 0, {231:231.0358842}
Uranium = "U", 92, 238.02891, 0, {238:238.0507884, 235:235.0439301, 234:234.0409523, 233:233.0396355, 236:236.0455682}
Neptunium = "Np", 93, 237.0, 0, {236:236.04657, 237:237.0481736}
Plutonium = "Pu", 94, 244.0, 0, {238:238.0495601, 239:239.0521636, 240:240.0538138, 241:241.0568517, 242:242.0587428, 244:244.0642053}
Americium = "Am", 95, 243.0, 0, {241:241.0568293, 243:243.0613813}
Curium = "Cm", 96, 247.0, 0, {243:243.0613893, 244:244.0627528, 245:245.0654915, 246:246.0672238, 247:247.0703541, 248:248.0723499}
Berkelium = "Bk", 97, 247.0, 0, {247:247.0703073, 249:249.0749877}
Californium = "Cf", 98, 251.0, 0, {249:249.0748539, 250:250.0764062, 251:251.0795886, 252:252.0816272}
Einsteinium = "Es", 99, 252.0, 0, {252:252.08298}
Fermium = "Fm", 100, 257.0, 0, {257:257.0951061}
Mendelevium = "Md", 101, 258.0, 0, {258:258.0984315, 260:260.10365}
Nobelium = "No", 102, 259.0, 0, {259:259.10103}
Lawrencium = "Lr", 103, 262.0, 0, {262:262.10961}
Rutherfordium = "Rf", 104, 267.0, 4, {267:267.12179}
Dubnium = "Db", 105, 270.0, 5, {268:268.12567}
Seaborgium = "Sg", 106, 269.0, 6, {271:271.13393}
Bohrium = "Bh", 107, 270.0, 7, {272:272.13826}
Hassium = "Hs", 108, 270.0, 8, {270:270.13429}
Meitnerium = "Mt", 109, 278.0, 9, {276:276.15159}
Darmstadtium = "Ds", 110, 281.0, 10, {281:281.16451}
Roentgenium = "Rg", 111, 281.0, 11, {280:280.16514}
Copernicium = "Cn", 112, 285.0, 12, {285:285.17712}
Nihonium = "Nh", 113, 286.0, 13, {284:284.17873}
Flerovium = "Fl", 114, 289.0, 14, {289:289.19042}
Moscovium = "Mc", 115, 289.0, 15, {288:288.19274}
Livermorium = "Lv", 116, 293.0, 16, {293:293.20449}
Tennessine = "Ts", 117, 293.0, 17, {292:292.20746}
Oganesson = "Og", 118, 294.0, 18, {294:294.21392}
# Name Symbol Number Mass Group Isotopes
# Add aliases for each element.
# Once we can use features from Python 3.13, this will be replaced by
# the Enum sunder `_add_alias_`
Xx = Unknown
H = Hydrogen
He = Helium
Li = Lithium
Be = Beryllium
B = Boron
C = Carbon
N = Nitrogen
O = Oxygen
F = Fluorine
Ne = Neon
Na = Sodium
Mg = Magnesium
Al = Aluminum
Si = Silicon
P = Phosphorus
S = Sulfur
Cl = Chlorine
Ar = Argon
K = Potassium
Ca = Calcium
Sc = Scandium
Ti = Titanium
V = Vanadium
Cr = Chromium
Mn = Manganese
Fe = Iron
Co = Cobalt
Ni = Nickel
Cu = Copper
Zn = Zinc
Ga = Gallium
Ge = Germanium
As = Arsenic
Se = Selenium
Br = Bromine
Kr = Krypton
Rb = Rubidium
Sr = Strontium
Y = Yttrium
Zr = Zirconium
Nb = Niobium
Mo = Molybdenum
Tc = Technetium
Ru = Ruthenium
Rh = Rhodium
Pd = Palladium
Ag = Silver
Cd = Cadmium
In = Indium
Sn = Tin
Sb = Antimony
Te = Tellurium
I = Iodine
Xe = Xenon
Cs = Cesium
Ba = Barium
La = Lanthanum
Ce = Cerium
Pr = Praseodymium
Nd = Neodymium
Pm = Promethium
Sm = Samarium
Eu = Europium
Gd = Gadolinium
Tb = Terbium
Dy = Dysprosium
Ho = Holmium
Er = Erbium
Tm = Thulium
Yb = Ytterbium
Lu = Lutetium
Hf = Hafnium
Ta = Tantalum
W = Tungsten
Re = Rhenium
Os = Osmium
Ir = Iridium
Pt = Platinum
Au = Gold
Hg = Mercury
Tl = Thallium
Pb = Lead
Bi = Bismuth
Po = Polonium
At = Astatine
Rn = Radon
Fr = Francium
Ra = Radium
Ac = Actinium
Th = Thorium
Pa = Protactinium
U = Uranium
Np = Neptunium
Pu = Plutonium
Am = Americium
Cm = Curium
Bk = Berkelium
Cf = Californium
Es = Einsteinium
Fm = Fermium
Md = Mendelevium
No = Nobelium
Lr = Lawrencium
Rf = Rutherfordium
Db = Dubnium
Sg = Seaborgium
Bh = Bohrium
Hs = Hassium
Mt = Meitnerium
Ds = Darmstadtium
Rg = Roentgenium
Cn = Copernicium
Nh = Nihonium
Fl = Flerovium
Mc = Moscovium
Lv = Livermorium
Ts = Tennessine
Og = Oganesson
#end class Element
