Author: bugman
Date: Thu Aug 28 17:12:57 2014
New Revision: 25393
URL: http://svn.gna.org/viewcvs/relax?rev=25393&view=rev
Log:
Added all gyromagnetic ratio information from lib.physical_constants to
lib.periodic_table.
The Periodic_table.gyromagnetic_ratio() method has been added to allow this
value to be easily
returned.
Modified:
trunk/lib/periodic_table.py
Modified: trunk/lib/periodic_table.py
URL:
http://svn.gna.org/viewcvs/relax/trunk/lib/periodic_table.py?rev=25393&r1=25392&r2=25393&view=diff
==============================================================================
--- trunk/lib/periodic_table.py (original)
+++ trunk/lib/periodic_table.py Thu Aug 28 17:12:57 2014
@@ -40,6 +40,25 @@
from lib.errors import RelaxError
+def isotope_to_mass_symbol(isotope):
+ """Convert the given isotope to its mass number and atomic symbol.
+
+ @param isotope: The isotope name, e.g. '15N'.
+ @type isotope: str
+ @return: The mass number A and atomic symbol.
+ @rtype: int, str
+ """
+
+ # The mass number.
+ A = int(split('[A-Z]', id)[0])
+
+ # The atomic symbol.
+ symbol = process_symbol(split('[0-9]', id)[-1])
+
+ # Return the components.
+ return A, symbol
+
+
def process_mass(mass):
"""Process the given mass, handling ranges, unstable isotopes, and
uncertainties.
@@ -110,17 +129,21 @@
self.isotopes = []
- def _add_isotope(self, A=None, atomic_mass=None):
+ def _add_isotope(self, A=None, atomic_mass=None, spin=None,
gyromagnetic_ratio=None):
"""Add the isotope information for the element.
- @keyword A: The mass number of the isotope.
- @type A: int
- @keyword atomic_mass: The atomic mass of the isotope. This uses
the string notation with the uncertainty specified in brackets at the end.
- @type atomic_mass: str
+ @keyword A: The mass number of the isotope.
+ @type A: int
+ @keyword atomic_mass: The atomic mass of the isotope.
This uses the string notation with the uncertainty specified in brackets at
the end.
+ @type atomic_mass: str
+ @keyword spin: Nuclear spin or angular momentum of
the isotope in units of h/2pi.
+ @type spin: int or float
+ @keyword gyromagnetic_ratio: The nuclear gyromagnetic ratio.
+ @type gyromagnetic_ratio: float
"""
# Create a new isotope container.
- isotope = Isotope(A=A, atomic_mass=atomic_mass)
+ isotope = Isotope(A=A, atomic_mass=atomic_mass, spin=spin,
gyromagnetic_ratio=gyromagnetic_ratio)
# Store it in the element container.
self.isotopes.append(isotope)
@@ -130,18 +153,24 @@
class Isotope:
"""A special object for the element container for holding different
isotope information."""
- def __init__(self, A=None, atomic_mass=None):
+ def __init__(self, A=None, atomic_mass=None, spin=None,
gyromagnetic_ratio=None):
"""Set up the isotope object.
- @keyword A: The mass number of the isotope.
- @type A: int
- @keyword atomic_mass: The atomic mass of the isotope. This uses
the string notation with the uncertainty specified in brackets at the end.
- @type atomic_mass: str
+ @keyword A: The mass number of the isotope.
+ @type A: int
+ @keyword atomic_mass: The atomic mass of the isotope.
This uses the string notation with the uncertainty specified in brackets at
the end.
+ @type atomic_mass: str
+ @keyword spin: Nuclear spin or angular momentum of
the isotope in units of h/2pi.
+ @type spin: int or float
+ @keyword gyromagnetic_ratio: The nuclear gyromagnetic ratio.
+ @type gyromagnetic_ratio: float
"""
# Store the values.
self.A = A
self.atomic_mass = atomic_mass
+ self.spin = spin
+ self.gyromagnetic_ratio = gyromagnetic_ratio
@@ -213,11 +242,8 @@
# An isotope.
if search('[0-9]', id):
- # The mass number.
- A = int(split('[A-Z]', id)[0])
-
- # The atomic symbol.
- symbol = process_symbol(split('[0-9]', id)[-1])
+ # Convert to the mass number and atomic symbol.
+ A, symbol = isotope_to_mass_symbol(id)
# Get the isotope container.
isotope = self._get_isotope(symbol=symbol, A=A)
@@ -250,6 +276,26 @@
return process_mass(self[symbol].atomic_weight)
+ def gyromagnetic_ratio(isotope=None):
+ """Return the gyromagnetic ratio for the isotope.
+
+ @keyword isotope: The isotope name, e.g. '15N'.
+ @type isotope: str
+ @raises RelaxError: If the nucleus type is unknown.
+ @returns: The desired gyromagnetic ratio.
+ @rtype: float
+ """
+
+ # Convert to the mass number and atomic symbol.
+ A, symbol = isotope_to_mass_symbol(isotope)
+
+ # Get the isotope container.
+ isotope = self._get_isotope(symbol=symbol, A=A)
+
+ # Return the gyromagnetic ratio.
+ return isotope.gyromagnetic_ratio
+
+
def lookup_symbol(self, atomic_number=None):
"""Return the atomic symbol corresponding to the atomic number Z.
@@ -276,11 +322,14 @@
)
element._add_isotope(
A=1,
- atomic_mass="1.0078250322(6)"
+ atomic_mass="1.0078250322(6)",
+ spin = 1/2.,
+ gyromagnetic_ratio = 26.7522212 * 1e7 # Pales = 2.675198e+8
)
element._add_isotope(
A=2,
- atomic_mass="2.0141017781(8)"
+ atomic_mass="2.0141017781(8)",
+ spin = 1
)
# Helium.
@@ -356,7 +405,9 @@
)
element._add_isotope(
A=13,
- atomic_mass="13.003354835(2)"
+ atomic_mass="13.003354835(2)",
+ spin = 1/2.,
+ gyromagnetic_ratio = 6.728 * 1e7
)
# Nitrogen.
@@ -372,7 +423,9 @@
)
element._add_isotope(
A=15,
- atomic_mass="15.000108899(4)"
+ atomic_mass="15.000108899(4)",
+ spin = -1/2.,
+ gyromagnetic_ratio = -2.7126 * 1e7 # Pales = -2.7116e+7
)
# Oxygen.
@@ -388,7 +441,9 @@
)
element._add_isotope(
A=17,
- atomic_mass="16.999131757(5)"
+ atomic_mass="16.999131757(5)",
+ spin = 5/2.,
+ gyromagnetic_ratio = -3.628 * 1e7
)
element._add_isotope(
A=18,
@@ -500,7 +555,9 @@
)
element._add_isotope(
A=31,
- atomic_mass="30.973761998(5)"
+ atomic_mass="30.973761998(5)",
+ spin = 1/2.,
+ gyromagnetic_ratio = 10.841 * 1e7
)
# Sulfur.
r25393 - /trunk/lib/periodic_table.py