# [−]Struct lumol::energy::Torsion

pub struct Torsion {
pub k: f64,
pub delta: f64,
pub n: usize,
}

Torsion potential.

This potential is intended for use with dihedral angles, using a custom periodicity and multiple minima.

$$V(x) = k (1 + \cos(n x - \delta))$$

where $k$ is the force constant, $n$ the periodicity of the potential, and $\delta$ the equilibrium angle.

# Examples

let potential = Torsion { delta: PI / 2.0, k: 10.0, n: 3 };
assert_eq!(potential.energy(PI / 2.0), 0.0);
assert_eq!(potential.energy(PI / 3.0), 10.0);

assert!(potential.force(PI / 2.0).abs() < 1e-12);

## Fields

Force constant

Equilibrium value

Multiplicity of the potential

## Trait Implementations

### impl Potential for Torsion

#### fn energy(&self, phi: f64) -> f64

Get the energy corresponding to the variable x

#### fn force(&self, phi: f64) -> f64

Get the force norm corresponding to the variable x

### impl Clone for Torsion

#### fn clone(&self) -> Torsion

Returns a copy of the value. Read more

#### fn clone_from(&mut self, source: &Self)1.0.0[src]

Performs copy-assignment from source. Read more

### impl FromToml for Torsion

#### fn from_toml(table: &BTreeMap<String, Value>) -> Result<Torsion, Error>

Do the conversion from table to Self.

## Blanket Implementations

### impl<T> ToOwned for T where    T: Clone, [src]

#### fn to_owned(&self) -> T[src]

Creates owned data from borrowed data, usually by cloning. Read more

#### fn clone_into(&self, target: &mut T)[src]

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

### impl<T> From for T[src]

#### fn from(t: T) -> T[src]

Performs the conversion.

### impl<T, U> Into for T where    U: From<T>, [src]

#### fn into(self) -> U[src]

Performs the conversion.

### impl<T, U> TryFrom for T where    T: From<U>, [src]

#### type Error = !

🔬 This is a nightly-only experimental API. (try_from)

The type returned in the event of a conversion error.

#### fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]

🔬 This is a nightly-only experimental API. (try_from)

Performs the conversion.

### impl<T> Borrow for T where    T: ?Sized, [src]

#### ⓘImportant traits for &'a mut R### Important traits for &'a mut R impl<'a, R> Read for &'a mut R where    R: Read + ?Sized, impl<'a, W> Write for &'a mut W where    W: Write + ?Sized, impl<'a, I> Iterator for &'a mut I where    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;fn borrow(&self) -> &T[src]

Immutably borrows from an owned value. Read more

### impl<T, U> TryInto for T where    U: TryFrom<T>, [src]

#### type Error = <U as TryFrom<T>>::Error

🔬 This is a nightly-only experimental API. (try_from)

The type returned in the event of a conversion error.

#### fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>[src]

🔬 This is a nightly-only experimental API. (try_from)

Performs the conversion.

### impl<T> BorrowMut for T where    T: ?Sized, [src]

#### ⓘImportant traits for &'a mut R### Important traits for &'a mut R impl<'a, R> Read for &'a mut R where    R: Read + ?Sized, impl<'a, W> Write for &'a mut W where    W: Write + ?Sized, impl<'a, I> Iterator for &'a mut I where    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;fn borrow_mut(&mut self) -> &mut T[src]

Mutably borrows from an owned value. Read more

### impl<T> Any for T where    T: 'static + ?Sized, [src]

#### fn get_type_id(&self) -> TypeId[src]

🔬 This is a nightly-only experimental API. (get_type_id)

this method will likely be replaced by an associated static

Gets the TypeId of self. Read more

### impl<P> Potential for P where    P: 'static + Computation + Clone,

#### fn energy(&self, r: f64) -> f64

Get the energy corresponding to the variable x

#### fn force(&self, r: f64) -> f64

Get the force norm corresponding to the variable x