diff --git a/biojava-structure/src/main/java/org/biojava/nbio/structure/asa/AsaCalculator.java b/biojava-structure/src/main/java/org/biojava/nbio/structure/asa/AsaCalculator.java
index 8cb45ee7f5..19ece0ab72 100644
--- a/biojava-structure/src/main/java/org/biojava/nbio/structure/asa/AsaCalculator.java
+++ b/biojava-structure/src/main/java/org/biojava/nbio/structure/asa/AsaCalculator.java
@@ -442,6 +442,13 @@ int[][] findNeighborIndicesSpatialHashing() {
 			nbsIndices[entry.getKey()] = indicesArray;
 		}
 
+		// important: some atoms might have no neighbors at all: we need to initialise to empty arrays
+		for (int i=0; i<nbsIndices.length; i++) {
+			if (nbsIndices[i] == null) {
+				nbsIndices[i] = new int[0];
+			}
+		}
+
 		return nbsIndices;
 	}
 
@@ -450,7 +457,12 @@ Point3d[] getAtomCoords() {
 	}
 
 	private List<Contact> calcContacts() {
-		double maxRadius = maxValue(radii);
+		if (atomCoords.length == 0)
+			return new ArrayList<>();
+		double maxRadius = 0;
+		OptionalDouble optionalDouble = Arrays.stream(radii).max();
+		if (optionalDouble.isPresent())
+			maxRadius = optionalDouble.getAsDouble();
 		double cutoff = maxRadius + maxRadius + probe + probe;
 		logger.debug("Max radius is {}, cutoff is {}", maxRadius, cutoff);
 		Grid grid = new Grid(cutoff);
@@ -458,16 +470,6 @@ private List<Contact> calcContacts() {
 		return grid.getIndicesContacts();
 	}
 
-	private static double maxValue(double[] array) {
-		double max = array[0];
-		for (int i = 0; i < array.length; i++) {
-			if (array[i] > max) {
-				max = array[i];
-			}
-		}
-		return max;
-	}
-
 	private double calcSingleAsa(int i) {
 		Point3d atom_i = atomCoords[i];
 
diff --git a/biojava-structure/src/test/java/org/biojava/nbio/structure/asa/TestAsaCalc.java b/biojava-structure/src/test/java/org/biojava/nbio/structure/asa/TestAsaCalc.java
index 0b3b33384a..79598bd410 100644
--- a/biojava-structure/src/test/java/org/biojava/nbio/structure/asa/TestAsaCalc.java
+++ b/biojava-structure/src/test/java/org/biojava/nbio/structure/asa/TestAsaCalc.java
@@ -20,7 +20,14 @@
  */
 package org.biojava.nbio.structure.asa;
 
-import org.biojava.nbio.structure.*;
+import org.biojava.nbio.structure.AminoAcidImpl;
+import org.biojava.nbio.structure.Atom;
+import org.biojava.nbio.structure.AtomImpl;
+import org.biojava.nbio.structure.Element;
+import org.biojava.nbio.structure.Structure;
+import org.biojava.nbio.structure.StructureException;
+import org.biojava.nbio.structure.StructureIO;
+import org.biojava.nbio.structure.StructureTools;
 import org.biojava.nbio.structure.io.mmcif.ChemCompGroupFactory;
 import org.biojava.nbio.structure.io.mmcif.DownloadChemCompProvider;
 import static org.junit.Assert.*;
@@ -180,4 +187,75 @@ public void testPerformance() throws StructureException, IOException {
 		assertEquals(withoutSH, withSH, 0.000001);
 
 	}
+
+	@Test
+	public void testNoNeighborsIssue() {
+
+		Atom[] atoms = {
+				getAtom(1.0, 1.0, 1.0),
+				getAtom(10.0, 1.0, 1.0),
+				getAtom(13.0, 1.0, 1.0)
+		};
+
+		AsaCalculator asaCalc = new AsaCalculator(atoms,
+				AsaCalculator.DEFAULT_PROBE_SIZE,
+				1000, 1);
+
+		int[][] allNbsSh = asaCalc.findNeighborIndicesSpatialHashing();
+
+		int[][] allNbs = asaCalc.findNeighborIndices();
+
+		assertEquals(3, allNbs.length);
+		assertEquals(3, allNbsSh.length);
+
+		for (int indexToTest =0; indexToTest < asaCalc.getAtomCoords().length; indexToTest++) {
+			int[] nbsSh = allNbsSh[indexToTest];
+			int[] nbs = allNbs[indexToTest];
+
+			List<Integer> listOfMatchingIndices = new ArrayList<>();
+			for (int i = 0; i < nbsSh.length; i++) {
+				for (int j = 0; j < nbs.length; j++) {
+					if (nbs[j] == nbsSh[i]) {
+						listOfMatchingIndices.add(j);
+						break;
+					}
+				}
+			}
+
+			assertEquals(nbs.length, nbsSh.length);
+
+			assertEquals(nbs.length, listOfMatchingIndices.size());
+		}
+
+		// first atom should have no neighbors
+		assertEquals(0, allNbsSh[0].length);
+	}
+
+	private Atom getAtom(double x, double y, double z) {
+		Atom atom = new AtomImpl();
+		AminoAcidImpl g = new AminoAcidImpl();
+		g.setAminoType('A');
+		atom.setGroup(g);
+		atom.setName("CA");
+		atom.setElement(Element.C);
+		atom.setX(x);
+		atom.setY(y);
+		atom.setZ(z);
+		return atom;
+	}
+
+	@Test
+	public void testNoAtomsAsaCalc() {
+
+		// in case of no atoms at all, the calculation should not fail and return an empty array
+		Atom[] atoms = new Atom[0];
+
+		AsaCalculator asaCalc = new AsaCalculator(atoms,
+				AsaCalculator.DEFAULT_PROBE_SIZE,
+				1000, 1);
+		double[] asas = asaCalc.calculateAsas();
+		assertNotNull(asas);
+		assertEquals(0, asas.length);
+
+	}
 }