SphericalOrbital¶
-
class
sisl.
SphericalOrbital
(l, rf_or_func, q0=0.0, tag='', **kwargs)¶ Bases:
sisl.Orbital
An arbitrary orbital class where \(\phi(\mathbf r)=f(|\mathbf r|)Y_l^m(\theta,\varphi)\)
Note that in this case the used spherical harmonics is:
\[Y^m_l(\theta,\varphi) = (-1)^m\sqrt{\frac{2l+1}{4\pi} \frac{(l-m)!}{(l+m)!}} e^{i m \theta} P^m_l(\cos(\varphi))\]The resulting orbital is
\[\phi_{lmn}(\mathbf r) = f(|\mathbf r|) Y^m_l(\theta, \varphi)\]where typically \(f(|\mathbf r|)\equiv\phi_{ln}(|\mathbf r|)\). The above equation clarifies that this class is only intended for each \(l\), and that subsequent \(m\) orders may be extracted by altering the spherical harmonic. Also, the quantum number \(n\) is not necessary as that value is implicit in the \(\phi_{ln}(|\mathbf r|)\) function.
- Parameters
l (int) – azimuthal quantum number
rf_or_func (tuple of (r, f) or func) – radial components as a tuple/list, or the function which can interpolate to any R See
set_radial
for details.q0 (float, optional) – initial charge
tag (str, optional) – user defined tag
-
f
¶ interpolation function that returns f(r) for a given radius
- Type
func
Examples
>>> from scipy.interpolate import interp1d >>> orb = SphericalOrbital(1, (np.arange(10.), np.arange(10.))) >>> orb.equal(SphericalOrbital(1, interp1d(np.arange(10.), np.arange(10.), ... fill_value=(0., 0.), kind='cubic', bounds_error=False))) True
Attributes
__doc__
__hash__
__module__
__slots__
Methods
__delattr__
Implement delattr(self, name).
__dir__
Default dir() implementation.
__eq__
(other)Return self==value.
__format__
Default object formatter.
__ge__
Return self>=value.
__getattribute__
Return getattr(self, name).
__getstate__
()Return the state of this object
__gt__
Return self>value.
__init__
(l, rf_or_func[, q0, tag])Initialize spherical orbital object
__init_subclass__
This method is called when a class is subclassed.
__le__
Return self<=value.
__lt__
Return self<value.
__ne__
Return self!=value.
__new__
Create and return a new object.
__plot__
([harmonics, axes])Plot the orbital radial/spherical harmonics
__reduce__
Helper for pickle.
__reduce_ex__
Helper for pickle.
__repr__
()Return repr(self).
__setattr__
Implement setattr(self, name, value).
__setstate__
(d)Re-create the state of this object
__sizeof__
Size of object in memory, in bytes.
__str__
()A string representation of the object
__subclasshook__
Abstract classes can override this to customize issubclass().
copy
()Create an exact copy of this object
equal
(other[, psi, radial])Compare two orbitals by comparing their radius, and possibly the radial and psi functions
name
([tex])Return a named specification of the orbital (
tag
)psi
(r[, m])Calculate \(\phi(\mathbf R)\) at a given point (or more points)
psi_spher
(r, theta, phi[, m, cos_phi])Calculate \(\phi(|\mathbf R|, \theta, \phi)\) at a given point (in spherical coordinates)
radial
(r[, is_radius])Calculate the radial part of the wavefunction \(f(\mathbf R)\)
scale
(scale)Scale the orbital by extending R by
scale
set_radial
(*args, **kwargs)Update the internal radial function used as a \(f(|\mathbf r|)\)
spher
(theta, phi[, m, cos_phi])Calculate the spherical harmonics of this orbital at a given point (in spherical coordinates)
toAtomicOrbital
([m, n, Z, P, q0])Create a list of
AtomicOrbital
objectstoGrid
([precision, c, R, dtype, Z])Create a Grid with only this orbital wavefunction on it
toSphere
([center])Return a sphere with radius equal to the orbital size
-
R
¶
-
equal
(other, psi=False, radial=False)[source]¶ Compare two orbitals by comparing their radius, and possibly the radial and psi functions
-
f
¶
-
l
¶
-
psi
(r, m=0)[source]¶ Calculate \(\phi(\mathbf R)\) at a given point (or more points)
The position r is a vector from the origin of this orbital.
- Parameters
r (array_like of (:, 3)) – the vector from the orbital origin
m (int, optional) – magnetic quantum number, must be in range
-self.l <= m <= self.l
- Returns
basis function value at point r
- Return type
-
psi_spher
(r, theta, phi, m=0, cos_phi=False)[source]¶ Calculate \(\phi(|\mathbf R|, \theta, \phi)\) at a given point (in spherical coordinates)
This is equivalent to
psi
however, the input is given in spherical coordinates.- Parameters
r (array_like) – the radius from the orbital origin
theta (array_like) – azimuthal angle in the \(x-y\) plane (from \(x\))
phi (array_like) – polar angle from \(z\) axis
m (int, optional) – magnetic quantum number, must be in range
-self.l <= m <= self.l
cos_phi (bool, optional) – whether phi is actually \(cos(\phi)\) which will be faster because cos is not necessary to call.
- Returns
basis function value at point r
- Return type
-
q0
¶
-
radial
(r, is_radius=True)[source]¶ Calculate the radial part of the wavefunction \(f(\mathbf R)\)
The position r is a vector from the origin of this orbital.
- Parameters
r (array_like) – radius from the orbital origin, for
is_radius=False
r must be vectorsis_radius (bool, optional) – whether r is a vector or the radius
- Returns
radial orbital value at point r
- Return type
-
set_radial
(*args, **kwargs)[source]¶ Update the internal radial function used as a \(f(|\mathbf r|)\)
This can be called in several ways:
- set_radial(r, f)
which uses
scipy.interpolate.UnivariateSpline(r, f, k=3, s=0, ext=1, check_finite=False)
to define the interpolation function (see interp keyword). Here the maximum radius of the orbital is the maximum r value, regardless off(r)
is zero for smaller r.- set_radial(func)
which sets the interpolation function directly. The maximum orbital range is determined automatically to a precision of 0.0001 AA.
- Parameters
f (r,) – the radial positions and the radial function values at r.
func (callable) – a function which enables evaluation of the radial function. The function should accept a single array and return a single array.
interp (callable, optional) – When two non-keyword arguments are passed this keyword will be used. It is the interpolation function which should return the equivalent of func. By using this one can define a custom interpolation routine. It should accept two arguments,
interp(r, f)
and return a callable that returns interpolation values. See examples for different interpolation routines.
Examples
>>> from scipy import interpolate as interp >>> o = SphericalOrbital(1, lambda x:x) >>> r = np.linspace(0, 4, 300) >>> f = np.exp(-r) >>> def i_univariate(r, f): ... return interp.UnivariateSpline(r, f, k=3, s=0, ext=1, check_finite=False) >>> def i_interp1d(r, f): ... return interp.interp1d(r, f, kind='cubic', fill_value=(f[0], 0.), bounds_error=False) >>> def i_spline(r, f): ... from functools import partial ... tck = interp.splrep(r, f, k=3, s=0) ... return partial(interp.splev, tck=tck, der=0, ext=1) >>> R = np.linspace(0, 4, 400) >>> o.set_radial(r, f, interp=i_univariate) >>> f_univariate = o.f(R) >>> o.set_radial(r, f, interp=i_interp1d) >>> f_interp1d = o.f(R) >>> o.set_radial(r, f, interp=i_spline) >>> f_spline = o.f(R) >>> np.allclose(f_univariate, f_interp1d) True >>> np.allclose(f_univariate, f_spline) True
-
spher
(theta, phi, m=0, cos_phi=False)[source]¶ Calculate the spherical harmonics of this orbital at a given point (in spherical coordinates)
- Parameters
theta (array_like) – azimuthal angle in the \(x-y\) plane (from \(x\))
phi (array_like) – polar angle from \(z\) axis
m (int, optional) – magnetic quantum number, must be in range
-self.l <= m <= self.l
cos_phi (bool, optional) – whether phi is actually \(cos(\phi)\) which will be faster because cos is not necessary to call.
- Returns
spherical harmonics at angles \(\theta\) and \(\phi\) and given quantum number m
- Return type
-
tag
¶
-
toAtomicOrbital
(m=None, n=None, Z=1, P=False, q0=None)[source]¶ Create a list of
AtomicOrbital
objectsThis defaults to create a list of
AtomicOrbital
objects for every m (for m in -l:l). One may optionally specify the sub-set of m to retrieve.- Parameters
- Returns
AtomicOrbital (for passed m an atomic orbital will be returned)
list of AtomicOrbital (for each \(m\in[-l;l]\) an atomic orbital will be returned in the list)
-
toGrid
(precision=0.05, c=1.0, R=None, dtype=<class 'numpy.float64'>, Z=1)¶ Create a Grid with only this orbital wavefunction on it
- Parameters
precision (float, optional) – used separation in the
Grid
between voxels (in Ang)c (float or complex, optional) – coefficient for the orbital
R (float, optional) – box size of the grid (default to the orbital range)
dtype (numpy.dtype, optional) – the used separation in the
Grid
between voxelsZ (int, optional) – atomic number associated with the grid