PT for electrostatic interactions (#153)

* add mo typedef

* Adds property type for electrostatic energy

include/simde/energy/electrostatic_energy.hpp

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2024 NWChemEx-Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+#include <pluginplay/property_type/property_type.hpp>
+#include <simde/types.hpp>
+
+namespace simde {
+
+template<typename ObjectType, typename PotentialType>
+DECLARE_TEMPLATED_PROPERTY_TYPE(ElectrostaticEnergy, ObjectType, PotentialType);
+
+template<typename ObjectType, typename PotentialType>
+TEMPLATED_PROPERTY_TYPE_INPUTS(ElectrostaticEnergy, ObjectType, PotentialType) {
+    using object_type    = const ObjectType&;
+    using potential_type = const PotentialType&;
+    auto rv              = pluginplay::declare_input()
+                .add_field<object_type>("Objects")
+                .template add_field<potential_type>("Potential");
+    rv["Objects"].set_description("The objects interacting with the potential");
+    rv["Potential"].set_description(
+      "The electrostatic potential (or the objects generating the potential)");
+    return rv;
+}
+
+template<typename ObjectType, typename PotentialType>
+TEMPLATED_PROPERTY_TYPE_RESULTS(ElectrostaticEnergy, ObjectType,
+                                PotentialType) {
+    auto rv = pluginplay::declare_result().add_field<double>("Energy");
+    return rv;
+}
+
+using charge_charge_interaction =
+  ElectrostaticEnergy<type::charges, type::charges>;
+
+} // namespace simde

include/simde/energy/energy.hpp

@@ -22,4 +22,5 @@
 #pragma once
 
 #include <simde/energy/ao_energy.hpp>
+#include <simde/energy/electrostatic_energy.hpp>
 #include <simde/energy/total_energy.hpp>

include/simde/types.hpp

@@ -33,6 +33,9 @@ using tensor = tensorwrapper::Tensor;
 
 // --------------------- Fundamental Types -------------------------------------
 
+/// Typedef of the class used to hold a set of point charges
+using charges = chemist::Charges<double>;
+
 /// Typedef of the class used to describe an electron
 using electron = chemist::Electron;
 

tests/cxx/unit_tests/energy/energy.cpp

@@ -15,10 +15,19 @@
  */
 
 #include "../test_property_type.hpp"
-#include <simde/energy/total_energy.hpp>
+#include <simde/energy/energy.hpp>
 
 using namespace simde;
 
 TEST_CASE("TotalEnergy") {
     test_property_type<TotalEnergy>({"Chemical System"}, {"Energy"});
 }
+
+TEST_CASE("AOEnergy") {
+    test_property_type<AOEnergy>({"AOs", "Chemical System"}, {"Energy"});
+}
+
+TEST_CASE("ElectrostaticEnergy<charges, charges>") {
+    test_property_type<charge_charge_interaction>({"Objects", "Potential"},
+                                                  {"Energy"});
+}